Instruction:
作为 Java 安全专家，检测此代码中的安全漏洞：
## 内容1
### 文件路径：
graylog2-server/src/main/java/org/graylog2/commands/Server.java
### 代码内容：
package org.graylog2.commands;

import com.github.rvesse.airline.annotations.Command;
import com.github.rvesse.airline.annotations.Option;
import com.google.common.collect.ImmutableList;
import com.google.common.util.concurrent.Service;
import com.google.common.util.concurrent.ServiceManager;
import com.google.inject.Injector;
import com.google.inject.Module;
import com.google.inject.spi.Message;
import com.mongodb.MongoException;
import org.graylog.enterprise.EnterpriseModule;
import org.graylog.events.EventsModule;
import org.graylog.grn.GRNTypesModule;
import org.graylog.metrics.prometheus.PrometheusExporterConfiguration;
import org.graylog.metrics.prometheus.PrometheusMetricsModule;
import org.graylog.plugins.cef.CEFInputModule;
import org.graylog.plugins.map.MapWidgetModule;
import org.graylog.plugins.map.config.GeoIpProcessorConfig;
import org.graylog.plugins.netflow.NetFlowPluginModule;
import org.graylog.plugins.pipelineprocessor.PipelineConfig;
import org.graylog.plugins.sidecar.SidecarModule;
import org.graylog.plugins.views.ViewsBindings;
import org.graylog.plugins.views.ViewsConfig;
import org.graylog.plugins.views.search.rest.scriptingapi.ScriptingApiModule;
import org.graylog.plugins.views.search.searchfilters.module.SearchFiltersModule;
import org.graylog.scheduler.JobSchedulerConfiguration;
import org.graylog.scheduler.JobSchedulerModule;
import org.graylog.security.SecurityModule;
import org.graylog2.Configuration;
import org.graylog2.alerts.AlertConditionBindings;
import org.graylog2.audit.AuditActor;
import org.graylog2.audit.AuditBindings;
import org.graylog2.audit.AuditEventSender;
import org.graylog2.bindings.AlarmCallbackBindings;
import org.graylog2.bindings.ConfigurationModule;
import org.graylog2.bindings.ElasticsearchModule;
import org.graylog2.bindings.InitializerBindings;
import org.graylog2.bindings.MessageFilterBindings;
import org.graylog2.bindings.MessageOutputBindings;
import org.graylog2.bindings.MongoDBModule;
import org.graylog2.bindings.PasswordAlgorithmBindings;
import org.graylog2.bindings.PeriodicalBindings;
import org.graylog2.bindings.PersistenceServicesBindings;
import org.graylog2.bindings.ServerBindings;
import org.graylog2.bootstrap.Main;
import org.graylog2.bootstrap.ServerBootstrap;
import org.graylog2.cluster.NodeService;
import org.graylog2.cluster.leader.LeaderElectionService;
import org.graylog2.configuration.ElasticsearchClientConfiguration;
import org.graylog2.configuration.ElasticsearchConfiguration;
import org.graylog2.configuration.EmailConfiguration;
import org.graylog2.configuration.HttpConfiguration;
import org.graylog2.configuration.MongoDbConfiguration;
import org.graylog2.configuration.TLSProtocolsConfiguration;
import org.graylog2.configuration.VersionCheckConfiguration;
import org.graylog2.contentpacks.ContentPacksModule;
import org.graylog2.database.entities.ScopedEntitiesModule;
import org.graylog2.decorators.DecoratorBindings;
import org.graylog2.featureflag.FeatureFlags;
import org.graylog2.indexer.IndexerBindings;
import org.graylog2.indexer.retention.RetentionStrategyBindings;
import org.graylog2.indexer.rotation.RotationStrategyBindings;
import org.graylog2.inputs.transports.NettyTransportConfiguration;
import org.graylog2.messageprocessors.MessageProcessorModule;
import org.graylog2.migrations.MigrationsModule;
import org.graylog2.notifications.Notification;
import org.graylog2.notifications.NotificationService;
import org.graylog2.plugin.KafkaJournalConfiguration;
import org.graylog2.plugin.ServerStatus;
import org.graylog2.plugin.Tools;
import org.graylog2.plugin.system.NodeId;
import org.graylog2.rest.resources.system.ClusterConfigValidatorModule;
import org.graylog2.shared.UI;
import org.graylog2.shared.bindings.MessageInputBindings;
import org.graylog2.shared.bindings.ObjectMapperModule;
import org.graylog2.shared.bindings.RestApiBindings;
import org.graylog2.shared.journal.Journal;
import org.graylog2.shared.system.activities.Activity;
import org.graylog2.shared.system.activities.ActivityWriter;
import org.graylog2.storage.VersionAwareStorageModule;
import org.graylog2.system.processing.ProcessingStatusConfig;
import org.graylog2.system.shutdown.GracefulShutdown;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import javax.inject.Inject;
import javax.inject.Named;
import java.util.Arrays;
import java.util.Collection;
import java.util.EnumSet;
import java.util.List;
import java.util.Set;
import java.util.concurrent.TimeUnit;

import static org.graylog2.audit.AuditEventTypes.NODE_SHUTDOWN_INITIATE;

@Command(name = "server", description = "Start the Graylog server")
public class Server extends ServerBootstrap {
    private static final Logger LOG = LoggerFactory.getLogger(Server.class);

    protected static final Configuration configuration = new Configuration();
    private final HttpConfiguration httpConfiguration = new HttpConfiguration();
    private final ElasticsearchConfiguration elasticsearchConfiguration = new ElasticsearchConfiguration();
    private final ElasticsearchClientConfiguration elasticsearchClientConfiguration = new ElasticsearchClientConfiguration();
    private final EmailConfiguration emailConfiguration = new EmailConfiguration();
    private final MongoDbConfiguration mongoDbConfiguration = new MongoDbConfiguration();
    private final VersionCheckConfiguration versionCheckConfiguration = new VersionCheckConfiguration();
    private final KafkaJournalConfiguration kafkaJournalConfiguration = new KafkaJournalConfiguration();
    private final NettyTransportConfiguration nettyTransportConfiguration = new NettyTransportConfiguration();
    private final PipelineConfig pipelineConfiguration = new PipelineConfig();
    private final ViewsConfig viewsConfiguration = new ViewsConfig();
    private final ProcessingStatusConfig processingStatusConfig = new ProcessingStatusConfig();
    private final JobSchedulerConfiguration jobSchedulerConfiguration = new JobSchedulerConfiguration();
    private final PrometheusExporterConfiguration prometheusExporterConfiguration = new PrometheusExporterConfiguration();
    private final TLSProtocolsConfiguration tlsConfiguration = new TLSProtocolsConfiguration();
    private final GeoIpProcessorConfig geoIpProcessorConfig = new GeoIpProcessorConfig();

    public Server() {
        super("server", configuration);
    }

    public Server(String commandName) {
        super(commandName, configuration);
    }

    @Option(name = {"-l", "--local"}, description = "Run Graylog in local mode. Only interesting for Graylog developers.")
    private boolean local = false;

    public boolean isLocal() {
        return local;
    }

    @Override
    protected List<Module> getCommandBindings(FeatureFlags featureFlags) {
        final ImmutableList.Builder<Module> modules = ImmutableList.builder();
        modules.add(
                new VersionAwareStorageModule(),
                new ConfigurationModule(configuration),
                new MongoDBModule(),
                new ServerBindings(configuration, isMigrationCommand()),
                new ElasticsearchModule(),
                new PersistenceServicesBindings(),
                new MessageFilterBindings(),
                new MessageProcessorModule(),
                new AlarmCallbackBindings(),
                new InitializerBindings(),
                new MessageInputBindings(),
                new MessageOutputBindings(configuration, chainingClassLoader),
                new RotationStrategyBindings(elasticsearchConfiguration),
                new RetentionStrategyBindings(),
                new PeriodicalBindings(),
                new ObjectMapperModule(chainingClassLoader),
                new RestApiBindings(),
                new PasswordAlgorithmBindings(),
                new DecoratorBindings(),
                new AuditBindings(),
                new AlertConditionBindings(),
                new IndexerBindings(),
                new MigrationsModule(),
                new NetFlowPluginModule(),
                new CEFInputModule(),
                new SidecarModule(),
                new ContentPacksModule(),
                new ViewsBindings(),
                new JobSchedulerModule(),
                new EventsModule(),
                new EnterpriseModule(),
                new GRNTypesModule(),
                new SecurityModule(),
                new PrometheusMetricsModule(),
                new ClusterConfigValidatorModule(),
                new MapWidgetModule(),
                new SearchFiltersModule(),
                new ScopedEntitiesModule(),
                new ScriptingApiModule(featureFlags)
        );
        return modules.build();
    }

    @Override
    protected List<Object> getCommandConfigurationBeans() {
        return Arrays.asList(configuration,
                httpConfiguration,
                elasticsearchConfiguration,
                elasticsearchClientConfiguration,
                emailConfiguration,
                mongoDbConfiguration,
                versionCheckConfiguration,
                kafkaJournalConfiguration,
                nettyTransportConfiguration,
                pipelineConfiguration,
                viewsConfiguration,
                processingStatusConfig,
                jobSchedulerConfiguration,
                prometheusExporterConfiguration,
                tlsConfiguration,
                geoIpProcessorConfig);
    }

    @Override
    protected void startNodeRegistration(Injector injector) {
        // Register this node.
        final NodeService nodeService = injector.getInstance(NodeService.class);
        final ServerStatus serverStatus = injector.getInstance(ServerStatus.class);
        final ActivityWriter activityWriter = injector.getInstance(ActivityWriter.class);
        final LeaderElectionService leaderElectionService = injector.getInstance(LeaderElectionService.class);
        nodeService.registerServer(serverStatus.getNodeId().toString(),
                leaderElectionService.isLeader(),
                httpConfiguration.getHttpPublishUri(),
                Tools.getLocalCanonicalHostname());
        serverStatus.setLocalMode(isLocal());
        if (leaderElectionService.isLeader() && !nodeService.isOnlyLeader(serverStatus.getNodeId())) {
            LOG.warn("Detected another leader in the cluster. Retrying in {} seconds to make sure it is not "
                    + "an old stale instance.", TimeUnit.MILLISECONDS.toSeconds(configuration.getStaleLeaderTimeout()));
            try {
                Thread.sleep(configuration.getStaleLeaderTimeout());
            } catch (InterruptedException e) { /* nope */ }

            if (!nodeService.isOnlyLeader(serverStatus.getNodeId())) {
                // All devils here.
                String what = "Detected other leader node in the cluster! Starting as non-leader! "
                        + "This is a mis-configuration you should fix.";
                LOG.warn(what);
                activityWriter.write(new Activity(what, Server.class));

                final NotificationService notificationService = injector.getInstance(NotificationService.class);

                // remove legacy notification, if present
                //noinspection deprecation
                notificationService.fixed(notificationService.build().addType(Notification.Type.MULTI_MASTER));

                // Write a notification.
                Notification notification = notificationService.buildNow()
                        .addType(Notification.Type.MULTI_LEADER)
                        .addSeverity(Notification.Severity.URGENT);
                notificationService.publishIfFirst(notification);

                configuration.setIsLeader(false);
            } else {
                LOG.warn("Stale leader has gone. Starting as leader.");
            }
        }
    }

    private static class ShutdownHook implements Runnable {
        private final ActivityWriter activityWriter;
        private final ServiceManager serviceManager;
        private final NodeId nodeId;
        private final GracefulShutdown gracefulShutdown;
        private final AuditEventSender auditEventSender;
        private final Journal journal;
        private final Service leaderElectionService;

        @Inject
        public ShutdownHook(ActivityWriter activityWriter,
                            ServiceManager serviceManager,
                            NodeId nodeId,
                            GracefulShutdown gracefulShutdown,
                            AuditEventSender auditEventSender,
                            Journal journal,
                            @Named("LeaderElectionService") Service leaderElectionService) {
            this.activityWriter = activityWriter;
            this.serviceManager = serviceManager;
            this.nodeId = nodeId;
            this.gracefulShutdown = gracefulShutdown;
            this.auditEventSender = auditEventSender;
            this.journal = journal;
            this.leaderElectionService = leaderElectionService;
        }

        @Override
        public void run() {
            String msg = "SIGNAL received. Shutting down.";
            LOG.info(msg);
            activityWriter.write(new Activity(msg, Main.class));

            auditEventSender.success(AuditActor.system(nodeId), NODE_SHUTDOWN_INITIATE);

            gracefulShutdown.runWithoutExit();
            serviceManager.stopAsync().awaitStopped();

            leaderElectionService.stopAsync().awaitTerminated();

            // Some services might continue performing processing
            // after the Journal service being down. Therefore it's
            // important to flush the most actual journal offset value
            // right before shutting down to avoid repetitive processing
            // and duplicates.
            journal.flush();
        }
    }

    @Override
    protected Class<? extends Runnable> shutdownHook() {
        return ShutdownHook.class;
    }

    @Override
    protected void annotateInjectorExceptions(Collection<Message> messages) {
        super.annotateInjectorExceptions(messages);
        for (Message message : messages) {
            if (message.getCause() instanceof MongoException) {
                MongoException e = (MongoException) message.getCause();
                LOG.error(UI.wallString("Unable to connect to MongoDB. Is it running and the configuration correct?\n" +
                        "Details: " + e.getMessage()));
                System.exit(-1);
            }
        }
    }

    @Override
    protected Set<ServerStatus.Capability> capabilities() {
        if (configuration.isLeader()) {
            //noinspection deprecation
            return EnumSet.of(ServerStatus.Capability.SERVER, ServerStatus.Capability.MASTER);
        } else {
            return EnumSet.of(ServerStatus.Capability.SERVER);
        }
    }
}

## 内容2
### 文件路径：
graylog2-server/src/main/java/org/graylog2/lookup/adapters/DnsLookupDataAdapter.java
### 代码内容：
package org.graylog2.lookup.adapters;

import com.codahale.metrics.Counter;
import com.codahale.metrics.MetricRegistry;
import com.codahale.metrics.Timer;
import com.fasterxml.jackson.annotation.JsonAutoDetect;
import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.annotation.JsonTypeName;
import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
import com.google.auto.value.AutoValue;
import com.google.common.base.Strings;
import com.google.common.collect.ArrayListMultimap;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.Multimap;
import com.google.inject.assistedinject.Assisted;
import org.apache.commons.collections4.CollectionUtils;
import org.apache.commons.lang3.StringUtils;
import org.graylog.autovalue.WithBeanGetter;
import org.graylog2.lookup.adapters.dnslookup.ADnsAnswer;
import org.graylog2.lookup.adapters.dnslookup.DnsAnswer;
import org.graylog2.lookup.adapters.dnslookup.DnsClient;
import org.graylog2.lookup.adapters.dnslookup.DnsLookupType;
import org.graylog2.lookup.adapters.dnslookup.PtrDnsAnswer;
import org.graylog2.lookup.adapters.dnslookup.TxtDnsAnswer;
import org.graylog2.lookup.dto.DataAdapterDto;
import org.graylog2.plugin.lookup.LookupCachePurge;
import org.graylog2.plugin.lookup.LookupDataAdapter;
import org.graylog2.plugin.lookup.LookupDataAdapterConfiguration;
import org.graylog2.plugin.lookup.LookupResult;
import org.graylog2.shared.utilities.ExceptionUtils;
import org.joda.time.Duration;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import javax.annotation.Nullable;
import javax.inject.Inject;
import java.net.UnknownHostException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import java.util.Optional;
import java.util.concurrent.TimeUnit;

public class DnsLookupDataAdapter extends LookupDataAdapter {

    private static final Logger LOG = LoggerFactory.getLogger(DnsLookupDataAdapter.class);

    public static final String NAME = "dnslookup";

    private static final Duration REFRESH_INTERVAL_DURATION = Duration.ZERO;
    private static final String A_RECORD_LABEL = "A";
    private static final String AAAA_RECORD_LABEL = "AAAA";
    private static final String ERROR_COUNTER = "errors";
    private static final String RESULTS_FIELD = "results";
    private static final String RAW_RESULTS_FIELD = "raw_results";
    private static final String TIMER_RESOLVE_DOMAIN_NAME = "resolveDomainNameTime";
    private static final String TIMER_REVERSE_LOOKUP = "reverseLookupTime";
    private static final String TIMER_TEXT_LOOKUP = "textLookupTime";
    private DnsClient dnsClient;
    private final Config config;

    private final Counter errorCounter;

    // Timers exist for all request types, so that each can be troubleshot individually.
    private final Timer resolveDomainNameTimer;
    private final Timer reverseLookupTimer;
    private final Timer textLookupTimer;

    @Inject
    public DnsLookupDataAdapter(@Assisted("dto") DataAdapterDto dto,
                                MetricRegistry metricRegistry) {
        super(dto, metricRegistry);
        this.config = (Config) dto.config();
        this.errorCounter = metricRegistry.counter(MetricRegistry.name(getClass(), dto.id(), ERROR_COUNTER));
        this.resolveDomainNameTimer = metricRegistry.timer(MetricRegistry.name(getClass(), dto.id(), TIMER_RESOLVE_DOMAIN_NAME));
        this.reverseLookupTimer = metricRegistry.timer(MetricRegistry.name(getClass(), dto.id(), TIMER_REVERSE_LOOKUP));
        this.textLookupTimer = metricRegistry.timer(MetricRegistry.name(getClass(), dto.id(), TIMER_TEXT_LOOKUP));
    }

    @Override
    protected void doStart() {

        dnsClient = new DnsClient(config.requestTimeout());
        dnsClient.start(config.serverIps());
    }

    @Override
    protected void doStop() {

        dnsClient.stop();
    }

    /**
     * Not needed for the DNS Lookup adaptor.
     */
    @Override
    public Duration refreshInterval() {
        return REFRESH_INTERVAL_DURATION;
    }

    /**
     * Not needed for the DNS Lookup adaptor.
     */
    @Override
    protected void doRefresh(LookupCachePurge cachePurge) {

    }

    @Override
    protected LookupResult doGet(Object key) {

        final String trimmedKey = StringUtils.trimToNull(key.toString());
        if (trimmedKey == null) {
            LOG.debug("A blank key was supplied");
            return getEmptyResult();
        }

        LOG.debug("Beginning [{}] DNS resolution for key [{}]", config.lookupType(), trimmedKey);

        LookupResult lookupResult;
        switch (config.lookupType()) {
            case A:
                try (final Timer.Context ignored = resolveDomainNameTimer.time()) {
                    lookupResult = resolveIPv4AddressForHostname(trimmedKey);
                }
                break;
            case AAAA: {
                try (final Timer.Context ignored = resolveDomainNameTimer.time()) {
                    lookupResult = resolveIPv6AddressForHostname(trimmedKey);
                }
                break;
            }
            case A_AAAA: {
                try (final Timer.Context ignored = resolveDomainNameTimer.time()) {
                    lookupResult = resolveAllAddressesForHostname(trimmedKey);
                }
                break;
            }
            case PTR: {
                try (final Timer.Context ignored = reverseLookupTimer.time()) {
                    lookupResult = performReverseLookup(trimmedKey);
                }
                break;
            }
            case TXT: {
                try (final Timer.Context ignored = textLookupTimer.time()) {
                    lookupResult = performTextLookup(trimmedKey);
                }
                break;
            }
            default:
                throw new IllegalArgumentException(String.format(Locale.ENGLISH, "DnsLookupType [%s] is not supported", config.lookupType()));
        }

        LOG.debug("[{}] DNS resolution complete for key [{}]. Response [{}]", config.lookupType(), trimmedKey, lookupResult);

        return lookupResult;
    }

    /**
     * Provides both single and multiple addresses in LookupResult. This is because the purpose of a hostname
     * resolution request is to resolve to a single IP address (so that communication can be initiated with it).
     * We also resolve all addresses in case they are needed.
     */
    private LookupResult resolveIPv4AddressForHostname(Object key) {

        final List<ADnsAnswer> aDnsAnswers;
        try {
            aDnsAnswers = dnsClient.resolveIPv4AddressForHostname(key.toString(), false);
        } catch (UnknownHostException e) {
            return LookupResult.empty(); // UnknownHostException is a valid case when the DNS record does not exist. Do not log an error.
        } catch (Exception e) {
            LOG.error("Could not resolve [{}] records for hostname [{}]. Cause [{}]", A_RECORD_LABEL, key, ExceptionUtils.getRootCauseOrMessage(e));
            errorCounter.inc();
            return getEmptyResult();
        }

        if (CollectionUtils.isNotEmpty(aDnsAnswers)) {
            return buildLookupResult(aDnsAnswers);
        }

        LOG.debug("Could not resolve [{}] records for hostname [{}].", A_RECORD_LABEL, key);
        return getEmptyResult();
    }

    /**
     * Provides both single and multiple addresses in LookupResult. This is because the purpose of a hostname
     * resolution request is to resolve to a single IP address (so that communication can be initiated with it).
     * We also resolve all addresses in case they are needed.
     */
    private LookupResult resolveIPv6AddressForHostname(Object key) {

        final List<ADnsAnswer> aDnsAnswers;
        try {
            aDnsAnswers = dnsClient.resolveIPv6AddressForHostname(key.toString(), false);
        } catch (UnknownHostException e) {
            return getEmptyResult(); // UnknownHostException is a valid case when the DNS record does not exist. Do not log an error.
        } catch (Exception e) {
            LOG.error("Could not resolve [{}] records for hostname [{}]. Cause [{}]", AAAA_RECORD_LABEL, key, ExceptionUtils.getRootCauseOrMessage(e));
            errorCounter.inc();
            return getErrorResult();
        }

        if (CollectionUtils.isNotEmpty(aDnsAnswers)) {
            return buildLookupResult(aDnsAnswers);
        }

        LOG.debug("Could not resolve [{}] records for hostname [{}].", AAAA_RECORD_LABEL, key);
        return getEmptyResult();
    }

    private LookupResult buildLookupResult(List<ADnsAnswer> aDnsAnswers) {

        /* Provide both a single and multiValue addresses.
         * Always read the first entry and place in singleValue */
        final String singleValue = aDnsAnswers.get(0).ipAddress();
        LookupResult.Builder builder = LookupResult.builder()
                                                   .single(singleValue)
                                                   .multiValue(Collections.singletonMap(RESULTS_FIELD, aDnsAnswers))
                                                   .stringListValue(ADnsAnswer.convertToStringListValue(aDnsAnswers));

        assignMinimumTTL(aDnsAnswers, builder);

        return builder.build();
    }

    /**
     * Resolves all IPv4 and IPv6 addresses for the hostname. A single IP address will be returned in the singleValue
     * field (IPv4 address will be returned if present). All IPv4 and IPv6 addresses will be included in the multiValue
     * field.
     *
     * @param key a hostname
     */
    private LookupResult resolveAllAddressesForHostname(Object key) {

        try {
            List<ADnsAnswer> ip4Answers = new ArrayList<>();
            List<ADnsAnswer> ip6Answers = new ArrayList<>();

            // UnknownHostException is a valid case when the DNS record does not exist. Silently ignore and do not log an error.
            try {
                ip4Answers = dnsClient.resolveIPv4AddressForHostname(key.toString(), true); // Include IP version
            } catch (UnknownHostException e) {
            }

            try {
                ip6Answers = dnsClient.resolveIPv6AddressForHostname(key.toString(), true); // Include IP version
            } catch (UnknownHostException e) {
            }

            // Select answer for single value. Prefer use of IPv4 address. Only return IPv6 address if no IPv6 address found.
            final String singleValue;
            if (CollectionUtils.isNotEmpty(ip4Answers)) {
                singleValue = ip4Answers.get(0).ipAddress();
            } else if (CollectionUtils.isNotEmpty(ip6Answers)) {
                singleValue = ip6Answers.get(0).ipAddress();
            } else {
                LOG.debug("Could not resolve [A/AAAA] records hostname [{}].", key);
                return getEmptyResult();
            }

            final LookupResult.Builder builder = LookupResult.builder();
            if (StringUtils.isNotBlank(singleValue)) {
                builder.single(singleValue);
            }

            final List<ADnsAnswer> allAnswers = new ArrayList<>();
            allAnswers.addAll(ip4Answers);
            allAnswers.addAll(ip6Answers);

            if (CollectionUtils.isNotEmpty(allAnswers)) {
                builder.multiValue(Collections.singletonMap(RESULTS_FIELD, allAnswers)).stringListValue(ADnsAnswer.convertToStringListValue(allAnswers));
            }

            assignMinimumTTL(allAnswers, builder);

            return builder.build();
        } catch (Exception e) {
            LOG.error("Could not resolve [A/AAAA] records for hostname [{}]. Cause [{}]", key, ExceptionUtils.getRootCauseOrMessage(e));
            errorCounter.inc();
            return getErrorResult();
        }
    }

    private LookupResult performReverseLookup(Object key) {

        final PtrDnsAnswer dnsResponse;
        try {
            dnsResponse = dnsClient.reverseLookup(key.toString());
        } catch (Exception e) {
            LOG.error("Could not perform reverse DNS lookup for [{}]. Cause [{}]", key, ExceptionUtils.getRootCauseOrMessage(e));
            errorCounter.inc();
            return getErrorResult();
        }

        if (dnsResponse != null) {
            if (!Strings.isNullOrEmpty(dnsResponse.fullDomain())) {

                // Include answer in both single and multiValue fields.
                final Map<Object, Object> multiValueResults = new LinkedHashMap<>();
                multiValueResults.put(PtrDnsAnswer.FIELD_DOMAIN, dnsResponse.domain());
                multiValueResults.put(PtrDnsAnswer.FIELD_FULL_DOMAIN, dnsResponse.fullDomain());
                multiValueResults.put(PtrDnsAnswer.FIELD_DNS_TTL, dnsResponse.dnsTTL());

                final LookupResult.Builder builder = LookupResult.builder()
                        .single(dnsResponse.fullDomain())
                        .multiValue(multiValueResults)
                        .stringListValue(ImmutableList.of(dnsResponse.fullDomain()));

                if (config.hasOverrideTTL()) {
                    builder.cacheTTL(config.getCacheTTLOverrideMillis());
                } else {
                    builder.cacheTTL(dnsResponse.dnsTTL() * 1000);
                }

                return builder.build();
            }
        }

        LOG.debug("Could not perform reverse lookup on IP address [{}]. No PTR record was found.", key);
        return getEmptyResult();
    }

    private LookupResult performTextLookup(Object key) {

        /* Query all TXT records for hostname and provide them in the multiValue field as an array.
         * Do not attempt to attempt to choose a single value for the user (all are valid). */
        final List<TxtDnsAnswer> txtDnsAnswers;
        try {
            txtDnsAnswers = dnsClient.txtLookup(key.toString());
        } catch (Exception e) {
            LOG.error("Could not perform TXT DNS lookup for [{}]. Cause [{}]", key, ExceptionUtils.getRootCauseOrMessage(e));
            errorCounter.inc();
            return getErrorResult();
        }

        if (CollectionUtils.isNotEmpty(txtDnsAnswers)) {
            final LookupResult.Builder builder = LookupResult.builder();
            builder.multiValue(Collections.singletonMap(RAW_RESULTS_FIELD, txtDnsAnswers))
                    .stringListValue(TxtDnsAnswer.convertToStringListValue(txtDnsAnswers));
            assignMinimumTTL(txtDnsAnswers, builder);

            return builder.build();
        }

        LOG.debug("Could not perform Text lookup on IP address [{}]. No TXT records were found.", key);
        return getEmptyResult();
    }

    /**
     * Assigns the minimum TTL found in the supplied DnsAnswers. The minimum makes sense, because this is the least
     * amount of time that at least one of the records is valid for.
     */
    private void assignMinimumTTL(List<? extends DnsAnswer> dnsAnswers, LookupResult.Builder builder) {

        if (config.hasOverrideTTL()) {
            builder.cacheTTL(config.getCacheTTLOverrideMillis());
        } else {
            // Deduce minimum TTL on all TXT records. A TTL will always be returned by DNS server.
            builder.cacheTTL(dnsAnswers.stream()
                                       .map(DnsAnswer::dnsTTL)
                                       .min(Comparator.comparing(Long::valueOf)).get() * 1000);
        }
    }

    @Override
    public void set(Object key, Object value) {
        throw new UnsupportedOperationException();
    }

    public interface Factory extends LookupDataAdapter.Factory2<DnsLookupDataAdapter> {
        @Override
        DnsLookupDataAdapter create(@Assisted("dto") DataAdapterDto dto);

        @Override
        DnsLookupDataAdapter.Descriptor getDescriptor();
    }

    public static class Descriptor extends LookupDataAdapter.Descriptor<Config> {
        public Descriptor() {
            super(NAME, DnsLookupDataAdapter.Config.class);
        }

        @Override
        public DnsLookupDataAdapter.Config defaultConfiguration() {
            return DnsLookupDataAdapter.Config.builder()
                                              .type(NAME)
                                              .lookupType(Config.DEFAULT_LOOKUP_TYPE)
                                              .serverIps(Config.DEFAULT_SERVER_IP)
                                              .cacheTTLOverrideEnabled(Config.DEFAULT_CACHE_TTL_OVERRIDE)
                                              .requestTimeout(Config.DEFAULT_TIMEOUT_MILLIS)
                                              .build();
        }
    }

    @AutoValue
    @WithBeanGetter
    @JsonAutoDetect
    @JsonDeserialize(builder = DnsLookupDataAdapter.Config.Builder.class)
    @JsonTypeName(NAME)
    public static abstract class Config implements LookupDataAdapterConfiguration {

        // Fields
        private static final String FIELD_CACHE_TTL_OVERRIDE = "cache_ttl_override";
        private static final String FIELD_CACHE_TTL_OVERRIDE_ENABLED = "cache_ttl_override_enabled";
        private static final String FIELD_CACHE_TTL_OVERRIDE_UNIT = "cache_ttl_override_unit";
        private static final String FIELD_LOOKUP_TYPE = "lookup_type";
        private static final String FIELD_REQUEST_TIMEOUT = "request_timeout";
        private static final String FIELD_SERVER_IPS = "server_ips";

        // Default values
        private static final boolean DEFAULT_CACHE_TTL_OVERRIDE = false;
        private static final DnsLookupType DEFAULT_LOOKUP_TYPE = DnsLookupType.A;
        private static final int DEFAULT_TIMEOUT_MILLIS = 10000;
        private static final String DEFAULT_SERVER_IP = ""; // Intentionally blank

        @Override
        @JsonProperty(TYPE_FIELD)
        public abstract String type();

        @JsonProperty(FIELD_LOOKUP_TYPE)
        public abstract DnsLookupType lookupType();

        @JsonProperty(FIELD_SERVER_IPS)
        public abstract String serverIps();

        @JsonProperty(FIELD_REQUEST_TIMEOUT)
        public abstract int requestTimeout();

        @JsonProperty(FIELD_CACHE_TTL_OVERRIDE_ENABLED)
        public abstract boolean cacheTTLOverrideEnabled();

        @Nullable
        @JsonProperty(FIELD_CACHE_TTL_OVERRIDE)
        public abstract Long cacheTTLOverride();

        @Nullable
        @JsonProperty(FIELD_CACHE_TTL_OVERRIDE_UNIT)
        public abstract TimeUnit cacheTTLOverrideUnit();

        public static Builder builder() {
            return new AutoValue_DnsLookupDataAdapter_Config.Builder();
        }

        @Override
        public Optional<Multimap<String, String>> validate() {

            final ArrayListMultimap<String, String> errors = ArrayListMultimap.create();
            if (StringUtils.isNotBlank(serverIps()) && !DnsClient.allIpAddressesValid(serverIps())) {
                errors.put(FIELD_SERVER_IPS, "Invalid server IP address and/or port. " +
                                             "Please enter one or more comma-separated IPv4 addresses with optional ports (eg. 192.168.1.1:5353, 192.168.1.244).");
            }

            if (requestTimeout() < 1) {
                errors.put(FIELD_REQUEST_TIMEOUT, "Value cannot be smaller than 1");
            }

            return errors.isEmpty() ? Optional.empty() : Optional.of(errors);
        }

        private boolean hasOverrideTTL() {

            return cacheTTLOverride() != null && cacheTTLOverrideUnit() != null;
        }

        private Long getCacheTTLOverrideMillis() {

            // Valid default, because Cache DNS_TTL is always required.
            if (!cacheTTLOverrideEnabled() || cacheTTLOverride() == null || cacheTTLOverrideUnit() == null) {
                return Long.MAX_VALUE;
            }

            return cacheTTLOverrideUnit().toMillis(cacheTTLOverride());
        }

        @AutoValue.Builder
        public abstract static class Builder {

            @JsonCreator
            public static Builder create() {
                return Config.builder()
                             .serverIps(DEFAULT_SERVER_IP)
                             .lookupType(DnsLookupType.A)
                             .cacheTTLOverrideEnabled(DEFAULT_CACHE_TTL_OVERRIDE)
                             .requestTimeout(DEFAULT_TIMEOUT_MILLIS);
            }

            @JsonProperty(TYPE_FIELD)
            public abstract Builder type(String type);

            @JsonProperty(FIELD_LOOKUP_TYPE)
            public abstract Builder lookupType(DnsLookupType lookupType);

            @JsonProperty(FIELD_SERVER_IPS)
            public abstract Builder serverIps(String serverIp);

            @JsonProperty(FIELD_REQUEST_TIMEOUT)
            public abstract Builder requestTimeout(int requestTimeout);

            @JsonProperty(FIELD_CACHE_TTL_OVERRIDE_ENABLED)
            public abstract Builder cacheTTLOverrideEnabled(boolean cacheTTLOverride);

            @JsonProperty(FIELD_CACHE_TTL_OVERRIDE)
            public abstract Builder cacheTTLOverride(Long cacheTTLOverride);

            @JsonProperty(FIELD_CACHE_TTL_OVERRIDE_UNIT)
            public abstract Builder cacheTTLOverrideUnit(@Nullable TimeUnit cacheTTLOverrideUnit);

            abstract Config autoBuild();

            public Config build() {

                return autoBuild();
            }
        }
    }
}

## 内容3
### 文件路径：
graylog2-server/src/main/java/org/graylog2/lookup/adapters/dnslookup/DnsClient.java
### 代码内容：
package org.graylog2.lookup.adapters.dnslookup;

import com.google.common.base.Joiner;
import com.google.common.base.Splitter;
import com.google.common.base.Strings;
import com.google.common.collect.Lists;
import com.google.common.net.HostAndPort;
import com.google.common.net.InetAddresses;
import com.google.common.net.InternetDomainName;
import io.netty.buffer.ByteBuf;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.nio.NioDatagramChannel;
import io.netty.handler.codec.dns.DefaultDnsPtrRecord;
import io.netty.handler.codec.dns.DefaultDnsQuestion;
import io.netty.handler.codec.dns.DefaultDnsRawRecord;
import io.netty.handler.codec.dns.DefaultDnsRecordDecoder;
import io.netty.handler.codec.dns.DnsRecord;
import io.netty.handler.codec.dns.DnsRecordType;
import io.netty.handler.codec.dns.DnsResponse;
import io.netty.handler.codec.dns.DnsSection;
import io.netty.resolver.dns.DnsNameResolver;
import io.netty.resolver.dns.DnsNameResolverBuilder;
import io.netty.resolver.dns.DnsServerAddressStreamProvider;
import io.netty.resolver.dns.SequentialDnsServerAddressStreamProvider;
import io.netty.util.concurrent.Future;
import org.apache.commons.collections4.CollectionUtils;
import org.apache.commons.lang3.StringUtils;
import org.graylog2.shared.utilities.ExceptionUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.net.Inet4Address;
import java.net.Inet6Address;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.UnknownHostException;
import java.util.ArrayList;
import java.util.List;
import java.util.Locale;
import java.util.Objects;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
import java.util.regex.Pattern;
import java.util.stream.Collectors;
import java.util.stream.StreamSupport;

public class DnsClient {

    private static final Logger LOG = LoggerFactory.getLogger(DnsClient.class);

    private static final int DEFAULT_DNS_PORT = 53;
    private static final int DEFAULT_REQUEST_TIMEOUT_INCREMENT = 100;
    private static final Pattern VALID_HOSTNAME_PATTERN = Pattern.compile("^(([a-zA-Z0-9]|[a-zA-Z0-9][a-zA-Z0-9\\-]*[a-zA-Z0-9])\\.)*([A-Za-z0-9]|[A-Za-z0-9][A-Za-z0-9\\-]*[A-Za-z0-9])$");

    // Use fully qualified reverse lookup domain names (with dot at end).
    private static final String IP_4_REVERSE_SUFFIX = ".in-addr.arpa.";
    private static final String IP_6_REVERSE_SUFFIX = ".ip6.arpa.";

    private static final String IP_4_VERSION = "IPv4";
    private static final String IP_6_VERSION = "IPv6";

    // Used to convert binary IPv6 address to hex.
    private static final char[] HEX_CHARS_ARRAY = "0123456789ABCDEF".toCharArray();
    private final long queryTimeout;
    private final long requestTimeout;

    private NioEventLoopGroup nettyEventLoop;
    private DnsNameResolver resolver;

    /**
     * Creates a new DNS client with the given query timeout. The request timeout will be the query timeout plus
     * the {@link #DEFAULT_REQUEST_TIMEOUT_INCREMENT}.
     *
     * @param queryTimeout the query timeout
     * @see #DnsClient(long, long)
     */
    public DnsClient(long queryTimeout) {
        this(queryTimeout, queryTimeout + DEFAULT_REQUEST_TIMEOUT_INCREMENT);
    }

    /**
     * Creates a new DNS client with the given query and request timeout. The query timeout is the maximum time to
     * wait for a DNS response from a DNS server. The request timeout is the maximum time to wait for the DNS request
     * completion. The request timeout should always be higher than the query timeout.
     *
     * Background: The request timeout is used to avoid blocking a thread by waiting for the DNS resolve future to
     * complete. This can happen when the {@link DnsNameResolver} is closed, and the event loop is shut down while
     * a resolver request is still running.
     *
     * @param queryTimeout   the query timeout
     * @param requestTimeout the request timeout
     */
    public DnsClient(long queryTimeout, long requestTimeout) {
        this.queryTimeout = queryTimeout;
        this.requestTimeout = requestTimeout;
    }

    public void start(String dnsServerIps) {

        LOG.debug("Attempting to start DNS client");
        final List<InetSocketAddress> iNetDnsServerIps = parseServerIpAddresses(dnsServerIps);

        nettyEventLoop = new NioEventLoopGroup();

        final DnsNameResolverBuilder dnsNameResolverBuilder = new DnsNameResolverBuilder(nettyEventLoop.next());
        dnsNameResolverBuilder.channelType(NioDatagramChannel.class).queryTimeoutMillis(queryTimeout);

        // Specify custom DNS servers if provided. If not, use those specified in local network adapter settings.
        if (CollectionUtils.isNotEmpty(iNetDnsServerIps)) {

            LOG.debug("Attempting to start DNS client with server IPs [{}] on port [{}] with timeout [{}]",
                      dnsServerIps, DEFAULT_DNS_PORT, requestTimeout);

            final DnsServerAddressStreamProvider dnsServer = new SequentialDnsServerAddressStreamProvider(iNetDnsServerIps);
            dnsNameResolverBuilder.nameServerProvider(dnsServer);
        } else {
            LOG.debug("Attempting to start DNS client with the local network adapter DNS server address on port [{}] with timeout [{}]",
                      DEFAULT_DNS_PORT, requestTimeout);
        }

        resolver = dnsNameResolverBuilder.build();

        LOG.debug("DNS client startup successful");
    }

    private List<InetSocketAddress> parseServerIpAddresses(String dnsServerIps) {

        // Parse and prepare DNS server IP addresses for Netty.
        return StreamSupport
                // Split comma-separated sever IP:port combos.
                .stream(Splitter.on(",").trimResults().omitEmptyStrings().split(dnsServerIps).spliterator(), false)
                // Parse as HostAndPort objects (allows convenient handling of port provided after colon).
                .map(hostAndPort -> HostAndPort.fromString(hostAndPort).withDefaultPort(DnsClient.DEFAULT_DNS_PORT))
                // Convert HostAndPort > InetSocketAddress as required by Netty.
                .map(hostAndPort -> new InetSocketAddress(hostAndPort.getHost(), hostAndPort.getPort()))
                .collect(Collectors.toList());
    }

    public void stop() {

        LOG.debug("Attempting to stop DNS client");

        if (nettyEventLoop == null) {
            LOG.error("DNS resolution event loop not initialized");
            return;
        }

        // Make sure to close the resolver before shutting down the event loop
        resolver.close();

        // Shutdown event loop (required by Netty).
        final Future<?> shutdownFuture = nettyEventLoop.shutdownGracefully();
        shutdownFuture.addListener(future -> LOG.debug("DNS client shutdown successful"));
    }

    public List<ADnsAnswer> resolveIPv4AddressForHostname(String hostName, boolean includeIpVersion)
            throws InterruptedException, ExecutionException, UnknownHostException {

        return resolveIpAddresses(hostName, DnsRecordType.A, includeIpVersion);
    }

    public List<ADnsAnswer> resolveIPv6AddressForHostname(String hostName, boolean includeIpVersion)
            throws InterruptedException, ExecutionException, UnknownHostException {

        return resolveIpAddresses(hostName, DnsRecordType.AAAA, includeIpVersion);
    }

    private List<ADnsAnswer> resolveIpAddresses(String hostName, DnsRecordType dnsRecordType, boolean includeIpVersion)
            throws InterruptedException, ExecutionException {

        LOG.debug("Attempting to resolve [{}] records for [{}]", dnsRecordType, hostName);

        if (isShutdown()) {
            throw new DnsClientNotRunningException();
        }

        validateHostName(hostName);

        final DefaultDnsQuestion aRecordDnsQuestion = new DefaultDnsQuestion(hostName, dnsRecordType);

        /* The DnsNameResolver.resolveAll(DnsQuestion) method handles all redirects through CNAME records to
         * ultimately resolve a list of IP addresses with TTL values. */
        try {
            return resolver.resolveAll(aRecordDnsQuestion).get(requestTimeout, TimeUnit.MILLISECONDS).stream()
                           .map(dnsRecord -> decodeDnsRecord(dnsRecord, includeIpVersion))
                           .filter(Objects::nonNull) // Removes any entries which the IP address could not be extracted for.
                           .collect(Collectors.toList());
        } catch (TimeoutException e) {
            throw new ExecutionException("Resolver future didn't return a result in " + requestTimeout + " ms", e);
        }
    }

    /**
     * Picks out the IP address and TTL from the answer response for each record.
     */
    private static ADnsAnswer decodeDnsRecord(DnsRecord dnsRecord, boolean includeIpVersion) {

        if (dnsRecord == null) {
            return null;
        }

        LOG.trace("Attempting to decode DNS record [{}]", dnsRecord);

        /* Read data from DNS record response. The data is a binary representation of the IP address
         * IPv4 address: 32 bits, IPv6 address: 128 bits */
        byte[] ipAddressBytes;
        final DefaultDnsRawRecord dnsRawRecord = (DefaultDnsRawRecord) dnsRecord;
        try {
            final ByteBuf byteBuf = dnsRawRecord.content();
            ipAddressBytes = new byte[byteBuf.readableBytes()];
            int readerIndex = byteBuf.readerIndex();
            byteBuf.getBytes(readerIndex, ipAddressBytes);
        } finally {
            /* Must manually release references on dnsRawRecord object since the DefaultDnsRawRecord class
             * extends ReferenceCounted. This also releases the above ByteBuf, since DefaultDnsRawRecord is
             * the holder for it. */
            dnsRawRecord.release();
        }

        LOG.trace("The IP address has [{}] bytes", ipAddressBytes.length);

        InetAddress ipAddress;
        try {
            ipAddress = InetAddress.getByAddress(ipAddressBytes); // Takes care of correctly creating an IPv4 or IPv6 address.
        } catch (UnknownHostException e) {
            // This should not happen.
            LOG.error("Could not extract IP address from DNS entry [{}]. Cause [{}]", dnsRecord.toString(), ExceptionUtils.getRootCauseMessage(e));
            return null;
        }

        LOG.trace("The resulting IP address is [{}]", ipAddress.getHostAddress());

        final ADnsAnswer.Builder builder = ADnsAnswer.builder()
                                                     .ipAddress(ipAddress.getHostAddress())
                                                     .dnsTTL(dnsRecord.timeToLive());

        if (includeIpVersion) {
            builder.ipVersion(ipAddress instanceof Inet4Address ? IP_4_VERSION : IP_6_VERSION);
        }

        return builder.build();
    }

    public PtrDnsAnswer reverseLookup(String ipAddress) throws InterruptedException, ExecutionException {

        LOG.debug("Attempting to perform reverse lookup for IP address [{}]", ipAddress);

        if (isShutdown()) {
            throw new DnsClientNotRunningException();
        }

        validateIpAddress(ipAddress);

        final String inverseAddressFormat = getInverseAddressFormat(ipAddress);

        DnsResponse content = null;
        try {
            content = resolver.query(new DefaultDnsQuestion(inverseAddressFormat, DnsRecordType.PTR)).get(requestTimeout, TimeUnit.MILLISECONDS).content();
            for (int i = 0; i < content.count(DnsSection.ANSWER); i++) {

                // Return the first PTR record, because there should be only one as per
                // http://tools.ietf.org/html/rfc1035#section-3.5
                final DnsRecord dnsRecord = content.recordAt(DnsSection.ANSWER, i);
                if (dnsRecord instanceof DefaultDnsPtrRecord) {

                    final DefaultDnsPtrRecord ptrRecord = (DefaultDnsPtrRecord) dnsRecord;
                    final PtrDnsAnswer.Builder dnsAnswerBuilder = PtrDnsAnswer.builder();

                    final String hostname = ptrRecord.hostname();
                    LOG.trace("PTR record retrieved with hostname [{}]", hostname);

                    try {
                        parseReverseLookupDomain(dnsAnswerBuilder, hostname);
                    } catch (IllegalArgumentException e) {
                        LOG.debug("Reverse lookup of [{}] was partially successful. The DNS server returned [{}], " +
                                  "which is an invalid host name. The \"domain\" field will be left blank.",
                                  ipAddress, hostname);
                        dnsAnswerBuilder.domain("");
                    }

                    return dnsAnswerBuilder.dnsTTL(ptrRecord.timeToLive())
                                           .build();
                }
            }
        } catch (TimeoutException e) {
            throw new ExecutionException("Resolver future didn't return a result in " + requestTimeout + " ms", e);
        } finally {
            if (content != null) {
                // Must manually release references on content object since the DnsResponse class extends ReferenceCounted
                content.release();
            }
        }

        return null;
    }

    /**
     * Extract the domain name (without subdomain). The Guava {@link InternetDomainName} implementation
     * provides a method to correctly handle this (and handles special cases for TLDs with multiple
     * names. eg. for lb01.store.amazon.co.uk, only amazon.co.uk would be extracted).
     * It uses https://publicsuffix.org behind the scenes.
     * <p>
     * Some domains (eg. completely randomly defined PTR domains) are not considered to have a public
     * suffix according to Guava. For those, the only option is to manually extract the domain with
     * string operations. This should be a rare case.
     */
    public static void parseReverseLookupDomain(PtrDnsAnswer.Builder dnsAnswerBuilder, String hostname) {

        dnsAnswerBuilder.fullDomain(hostname);

        final InternetDomainName internetDomainName = InternetDomainName.from(hostname);
        if (internetDomainName.hasPublicSuffix()) {

            // Use Guava to extract domain name.
            final InternetDomainName topDomainName = internetDomainName.topDomainUnderRegistrySuffix();
            dnsAnswerBuilder.domain(topDomainName.toString());
        } else {

            /* Manually extract domain name.
             * Eg. for hostname test.some-domain.com, only some-domain.com will be extracted. */
            String[] split = hostname.split("\\.");
            if (split.length > 1) {
                dnsAnswerBuilder.domain(split[split.length - 2] + "." + split[split.length - 1]);
            } else if (split.length == 1) {
                dnsAnswerBuilder.domain(hostname); // Domain is a single word with no dots.
            } else {
                dnsAnswerBuilder.domain(""); // Domain is blank.
            }
        }
    }

    public List<TxtDnsAnswer> txtLookup(String hostName) throws InterruptedException, ExecutionException {

        if (isShutdown()) {
            throw new DnsClientNotRunningException();
        }

        LOG.debug("Attempting to perform TXT lookup for hostname [{}]", hostName);

        validateHostName(hostName);

        DnsResponse content = null;
        try {
            content = resolver.query(new DefaultDnsQuestion(hostName, DnsRecordType.TXT)).get(requestTimeout, TimeUnit.MILLISECONDS).content();
            int count = content.count(DnsSection.ANSWER);
            final ArrayList<TxtDnsAnswer> txtRecords = new ArrayList<>(count);
            for (int i = 0; i < count; i++) {

                final DnsRecord dnsRecord = content.recordAt(DnsSection.ANSWER, i);
                LOG.trace("TXT record [{}] retrieved with content [{}].", i, dnsRecord);

                if (dnsRecord instanceof DefaultDnsRawRecord) {
                    final DefaultDnsRawRecord txtRecord = (DefaultDnsRawRecord) dnsRecord;

                    final TxtDnsAnswer.Builder dnsAnswerBuilder = TxtDnsAnswer.builder();
                    final String decodeTxtRecord = decodeTxtRecord(txtRecord);
                    LOG.trace("The decoded TXT record is [{}]", decodeTxtRecord);

                    dnsAnswerBuilder.value(decodeTxtRecord)
                                    .dnsTTL(txtRecord.timeToLive())
                                    .build();

                    txtRecords.add(dnsAnswerBuilder.build());
                }
            }

            return txtRecords;
        } catch (TimeoutException e) {
            throw new ExecutionException("Resolver future didn't return a result in " + requestTimeout + " ms", e);
        } finally {
            if (content != null) {
                // Must manually release references on content object since the DnsResponse class extends ReferenceCounted
                content.release();
            }
        }
    }

    private boolean isShutdown() {
        return nettyEventLoop == null || nettyEventLoop.isShutdown();
    }

    private static String decodeTxtRecord(DefaultDnsRawRecord record) {

        LOG.debug("Attempting to read TXT value from DNS record [{}]", record);

        return DefaultDnsRecordDecoder.decodeName(record.content());
    }

    public String getInverseAddressFormat(String ipAddress) {

        ipAddress = StringUtils.trim(ipAddress);

        validateIpAddress(ipAddress);

        LOG.debug("Preparing inverse format for IP address [{}]", ipAddress);

        // Detect what type of address is provided (IPv4 or IPv6)
        if (isIp6Address(ipAddress)) {

            LOG.debug("[{}] is an IPv6 address", ipAddress);

            /* Build reverse IPv6 address string with correct ip6.arpa suffix.
             * All hex nibbles from the full address should be reversed (with dots in between)
             * and the ip6.arpa suffix added to the end.
             *
             * For example, the reverse format for the address 2604:a880:800:10::7a1:b001 is
             * 1.0.0.b.1.a.7.0.0.0.0.0.0.0.0.0.0.1.0.0.0.0.8.0.0.8.8.a.4.0.6.2.ip6.arpa
             * See https://www.dnscheck.co/ptr-record-monitor for more info. */

            // Parse the full address as an InetAddress to allow the full address bytes (16 bytes/128 bits) to be obtained.
            final byte[] addressBytes = InetAddresses.forString(ipAddress).getAddress();

            if (addressBytes.length > 16) {
                throw new IllegalArgumentException(String.format(Locale.ENGLISH, "[%s] is an invalid IPv6 address", ipAddress));
            }

            // Convert the raw address bytes to hex.
            final char[] resolvedHex = new char[addressBytes.length * 2];
            for (int i = 0; i < addressBytes.length; i++) {
                final int v = addressBytes[i] & 0xFF;
                resolvedHex[i * 2] = HEX_CHARS_ARRAY[v >>> 4];
                resolvedHex[i * 2 + 1] = HEX_CHARS_ARRAY[v & 0x0F];
            }

            final String fullHexAddress = new String(resolvedHex).toLowerCase(Locale.ENGLISH);
            final String[] reversedAndSplit = new StringBuilder(fullHexAddress).reverse().toString().split("");

            final String invertedAddress = Joiner.on(".").join(reversedAndSplit);

            LOG.debug("Inverted address [{}] built for [{}]", invertedAddress, ipAddress);

            return invertedAddress + IP_6_REVERSE_SUFFIX;
        } else {

            LOG.debug("[{}] is an IPv4 address", ipAddress);

            /* Build reverse IPv4 address string with correct in-addr.arpa suffix.
             * All octets should be reversed and the ip6.arpa suffix added to the end.
             *
             * For example, the reverse format for the address 10.20.30.40 is
             * 40.30.20.10.in-addr.arpa */
            final String[] octets = ipAddress.split("\\.");
            final String invertedAddress = octets[3] + "." + octets[2] + "." + octets[1] + "." + octets[0] + IP_4_REVERSE_SUFFIX;

            LOG.debug("Inverted address [{}] built for [{}]", invertedAddress, ipAddress);

            return invertedAddress;
        }
    }

    private void validateHostName(String hostName) {

        if (!isHostName(hostName)) {
            throw new IllegalArgumentException(
                    String.format(Locale.ENGLISH, "[%s] is an invalid hostname. Please supply a pure hostname (eg. api.graylog.com)",
                                  hostName));
        }
    }

    public static boolean isHostName(String hostName) {

        return VALID_HOSTNAME_PATTERN.matcher(hostName).matches();
    }

    private static void validateIpAddress(final String ipAddress) {

        if (!isValidIpAddress(ipAddress)) {
            throw new IllegalArgumentException(
                    String.format(Locale.ENGLISH, "[%s] is an invalid IP address.", ipAddress));
        }
    }

    private static boolean isValidIpAddress(String ipAddress) {

        return isIp4Address(ipAddress) || isIp6Address(ipAddress);
    }

    public static boolean isIp4Address(String ipAddress) {

        try {
            final InetAddress address = InetAddresses.forString(ipAddress);
            if (address instanceof Inet4Address) {
                return true;
            }
        } catch (IllegalArgumentException e) {
            // Absorb exception.
        }

        return false;
    }

    public static boolean isIp6Address(String ipAddress) {

        try {
            final InetAddress address = InetAddresses.forString(ipAddress);
            if (address instanceof Inet6Address) {
                return true;
            }
        } catch (IllegalArgumentException e) {
            // Absorb exception.
        }

        return false;
    }

    /**
     * @param ipAddresses A comma-separated list of IP addresses
     * @return true if all comma-separated IP addresses are valid
     * "8.8.4.4, 8.8.8.8" returns true
     * "8.8.4.4, " returns true
     * "8.8.4.4" returns true
     * "8.8.4.4 8.8.8.8" returns false
     * "8.8.4.4, google.com" returns false
     */
    public static boolean allIpAddressesValid(String ipAddresses) {

        if (!Strings.isNullOrEmpty(ipAddresses)) {
            return Lists.newArrayList(Splitter.on(",")
                                              .trimResults()
                                              .omitEmptyStrings()
                                              .split(ipAddresses)).stream()
                        .map(hostAndPort -> HostAndPort.fromString(hostAndPort).withDefaultPort(DnsClient.DEFAULT_DNS_PORT))
                        .allMatch(hostAndPort -> isValidIpAddress(hostAndPort.getHost()));
        }

        return false;
    }
}

Output:
【漏洞类型】DNS源端口固定问题
【严重性】High
【漏洞摘要】Graylog的DNS查询使用了固定的源端口，这可能导致网络攻击者通过跟踪和预测源端口来执行DNS欺骗攻击。具体来说，`DnsClient`类在初始化Netty事件循环组时没有随机化源端口，而是使用了默认的端口。这使得攻击者可以轻松地预测和利用DNS查询的源端口，从而实施DNS欺骗攻击。
【关键代码模式】与DNS查询源端口固定的代码模式相关的关键函数和关键词包括`DnsClient`类的构造函数和初始化Netty事件循环组的方法。
【修复方法说明】通过引入DNS解析器池并为每个解析器分配随机的源端口，修复了DNS源端口固定的问题。这有助于防止DNS欺骗攻击，因为攻击者无法预测和预测每个DNS查询的源端口。


Instruction:
作为 Java 安全专家，检测此代码中的安全漏洞：
## 内容1
### 文件路径：
leshan-core/src/main/java/org/eclipse/leshan/core/model/DDFFileParser.java
### 代码内容：
package org.eclipse.leshan.core.model;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;

import org.eclipse.leshan.core.LwM2m.LwM2mVersion;
import org.eclipse.leshan.core.model.ResourceModel.Operations;
import org.eclipse.leshan.core.model.ResourceModel.Type;
import org.eclipse.leshan.core.util.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.w3c.dom.DOMException;
import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.SAXException;

/**
 * A parser for Object DDF files.
 */
public class DDFFileParser {

    private static final Logger LOG = LoggerFactory.getLogger(DDFFileParser.class);

    private final DocumentBuilderFactory factory;
    private final DDFFileValidatorFactory ddfValidatorFactory;
    private final DDFFileValidator ddfValidator;

    public DDFFileParser() {
        this(null, null);
    }

    /**
     * Build a DDFFileParser with a given {@link DDFFileValidator}.
     *
     * @param ddfValidator a {@link DDFFileValidator} or {@code null} if no validation required.
     * @since 1.1
     */
    public DDFFileParser(DDFFileValidator ddfValidator) {
        this(ddfValidator, null);
    }

    /**
     * Build a DDFFileParser with a given {@link DDFFileValidatorFactory}.
     *
     * @param ddfFileValidatorFactory a {@link DDFFileValidatorFactory} or {@code null} if no validation required.
     */
    public DDFFileParser(DDFFileValidatorFactory ddfFileValidatorFactory) {
        this(null, ddfFileValidatorFactory);
    }

    private DDFFileParser(DDFFileValidator ddfValidator, DDFFileValidatorFactory ddfFileValidatorFactory) {
        factory = DocumentBuilderFactory.newInstance();
        factory.setNamespaceAware(true);
        this.ddfValidator = ddfValidator;
        this.ddfValidatorFactory = ddfFileValidatorFactory;
    }

    /**
     * Parse a DDF file.
     *
     * @throws InvalidDDFFileException if DDF file is not a valid.
     * @throws IOException see {@link FileInputStream#FileInputStream(File)} or
     *         {@link DocumentBuilder#parse(InputStream)}
     */
    public List<ObjectModel> parse(File ddfFile) throws InvalidDDFFileException, IOException {
        try (InputStream input = new FileInputStream(ddfFile)) {
            return parse(input, ddfFile.getName());
        }
    }

    /**
     * Parse a DDF file from an inputstream.
     *
     * @throws InvalidDDFFileException if DDF file is not a valid.
     * @throws IOException see {@link FileInputStream#FileInputStream(File)} or
     *         {@link DocumentBuilder#parse(InputStream)}
     */
    public List<ObjectModel> parse(InputStream inputStream, String streamName)
            throws InvalidDDFFileException, IOException {
        streamName = streamName == null ? "" : streamName;

        LOG.debug("Parsing DDF file {}", streamName);

        try {
            // Parse XML file
            DocumentBuilder builder = factory.newDocumentBuilder();
            Document document = builder.parse(inputStream);

            // Get DDF file validator
            LwM2mVersion lwm2mVersion;
            DDFFileValidator ddfFileValidator;
            if (ddfValidatorFactory != null) {
                lwm2mVersion = ddfValidatorFactory.extractLWM2MVersion(document, streamName);
                ddfFileValidator = ddfValidatorFactory.create(lwm2mVersion);
            } else {
                lwm2mVersion = null;
                ddfFileValidator = ddfValidator;
            }

            // Validate XML against Schema
            boolean validateDdf = ddfFileValidator != null;
            if (validateDdf) {
                ddfFileValidator.validate(document);
            }

            // Build list of ObjectModel
            ArrayList<ObjectModel> objects = new ArrayList<>();
            NodeList nodeList = document.getDocumentElement().getElementsByTagName("Object");
            for (int i = 0; i < nodeList.getLength(); i++) {
                objects.add(parseObject(nodeList.item(i), streamName, lwm2mVersion, validateDdf));
            }
            return objects;
        } catch (InvalidDDFFileException | SAXException e) {
            throw new InvalidDDFFileException(e, "Invalid DDF file %s", streamName);
        } catch (ParserConfigurationException e) {
            throw new IllegalStateException("Unable to create Document Builder", e);
        }
    }

    private ObjectModel parseObject(Node object, String streamName, LwM2mVersion schemaVersion, boolean validate)
            throws InvalidDDFFileException {

        Node objectType = object.getAttributes().getNamedItem("ObjectType");
        if (validate && (objectType == null || !"MODefinition".equals(objectType.getTextContent()))) {
            throw new InvalidDDFFileException(
                    "Object element in %s MUST have a ObjectType attribute equals to 'MODefinition'.", streamName);
        }

        Integer id = null;
        String name = null;
        String description = null;
        String version = ObjectModel.DEFAULT_VERSION;
        Boolean multiple = null;
        Boolean mandatory = null;
        Map<Integer, ResourceModel> resources = new LinkedHashMap<>();
        String urn = null;
        String description2 = null;
        String lwm2mVersion = LwM2mVersion.getDefault().toString();

        for (int i = 0; i < object.getChildNodes().getLength(); i++) {
            Node field = object.getChildNodes().item(i);
            if (field.getNodeType() != Node.ELEMENT_NODE)
                continue;

            switch (field.getNodeName()) {
            case "ObjectID":
                id = Integer.valueOf(field.getTextContent());
                break;
            case "Name":
                name = field.getTextContent();
                break;
            case "Description1":
                description = field.getTextContent();
                break;
            case "ObjectVersion":
                if (!StringUtils.isEmpty(field.getTextContent())) {
                    version = field.getTextContent();
                }
                break;
            case "MultipleInstances":
                if ("Multiple".equals(field.getTextContent())) {
                    multiple = true;
                } else if ("Single".equals(field.getTextContent())) {
                    multiple = false;
                }
                break;
            case "Mandatory":
                if ("Mandatory".equals(field.getTextContent())) {
                    mandatory = true;
                } else if ("Optional".equals(field.getTextContent())) {
                    mandatory = false;
                }
                break;
            case "Resources":
                for (int j = 0; j < field.getChildNodes().getLength(); j++) {
                    Node item = field.getChildNodes().item(j);
                    if (item.getNodeType() != Node.ELEMENT_NODE)
                        continue;

                    if (item.getNodeName().equals("Item")) {
                        ResourceModel resource = this.parseResource(item, streamName);
                        if (validate && resources.containsKey(resource.id)) {
                            throw new InvalidDDFFileException(
                                    "Object %s in %s contains at least 2 resources with same id %s.",
                                    id != null ? id : "", streamName, resource.id);
                        } else {
                            resources.put(resource.id, resource);
                        }
                    }
                }
                break;
            case "ObjectURN":
                urn = field.getTextContent();
                break;
            case "LWM2MVersion":
                if (!StringUtils.isEmpty(field.getTextContent())) {
                    lwm2mVersion = field.getTextContent();
                    if (schemaVersion != null && !schemaVersion.toString().equals(lwm2mVersion)) {
                        throw new InvalidDDFFileException(
                                "LWM2MVersion is not consistent with xml schema(xsi:noNamespaceSchemaLocation) in %s : %s  expected but was %s.",
                                streamName, schemaVersion, lwm2mVersion);
                    }
                }
                break;
            case "Description2":
                description2 = field.getTextContent();
                break;
            default:
                break;
            }
        }

        return new ObjectModel(id, name, description, version, multiple, mandatory, resources.values(), urn,
                lwm2mVersion, description2);

    }

    private ResourceModel parseResource(Node item, String streamName) throws DOMException, InvalidDDFFileException {

        Integer id = Integer.valueOf(item.getAttributes().getNamedItem("ID").getTextContent());
        String name = null;
        Operations operations = null;
        Boolean multiple = false;
        Boolean mandatory = false;
        Type type = null;
        String rangeEnumeration = null;
        String units = null;
        String description = null;

        for (int i = 0; i < item.getChildNodes().getLength(); i++) {
            Node field = item.getChildNodes().item(i);
            if (field.getNodeType() != Node.ELEMENT_NODE)
                continue;

            switch (field.getNodeName()) {
            case "Name":
                name = field.getTextContent();
                break;
            case "Operations":
                String strOp = field.getTextContent();
                if (strOp != null && !strOp.isEmpty()) {
                    operations = Operations.valueOf(strOp);
                } else {
                    operations = Operations.NONE;
                }
                break;
            case "MultipleInstances":
                if ("Multiple".equals(field.getTextContent())) {
                    multiple = true;
                } else if ("Single".equals(field.getTextContent())) {
                    multiple = false;
                }
                break;
            case "Mandatory":
                if ("Mandatory".equals(field.getTextContent())) {
                    mandatory = true;
                } else if ("Optional".equals(field.getTextContent())) {
                    mandatory = false;
                }
                break;
            case "Type":
                switch (field.getTextContent()) {
                case "String":
                    type = Type.STRING;
                    break;
                case "Integer":
                    type = Type.INTEGER;
                    break;
                case "Float":
                    type = Type.FLOAT;
                    break;
                case "Boolean":
                    type = Type.BOOLEAN;
                    break;
                case "Opaque":
                    type = Type.OPAQUE;
                    break;
                case "Time":
                    type = Type.TIME;
                    break;
                case "Objlnk":
                    type = Type.OBJLNK;
                    break;
                case "Unsigned Integer":
                    type = Type.UNSIGNED_INTEGER;
                    break;
                case "Corelnk":
                    type = Type.CORELINK;
                    break;
                case "":
                    type = Type.NONE;
                    break;
                default:
                    break;
                }
                break;
            case "RangeEnumeration":
                rangeEnumeration = field.getTextContent();
                break;
            case "Units":
                units = field.getTextContent();
                break;
            case "Description":
                description = field.getTextContent();
                break;
            default:
                break;
            }
        }
        return new ResourceModel(id, name, operations, multiple, mandatory, type, rangeEnumeration, units, description);
    }
}

## 内容2
### 文件路径：
leshan-core/src/main/java/org/eclipse/leshan/core/model/DefaultDDFFileValidator.java
### 代码内容：
package org.eclipse.leshan.core.model;

import java.io.IOException;
import java.io.InputStream;

import javax.xml.XMLConstants;
import javax.xml.transform.Source;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamSource;
import javax.xml.validation.Schema;
import javax.xml.validation.SchemaFactory;
import javax.xml.validation.Validator;

import org.eclipse.leshan.core.LwM2m.LwM2mVersion;
import org.eclipse.leshan.core.util.Validate;
import org.w3c.dom.Node;
import org.xml.sax.SAXException;

/**
 * A DDF File Validator.
 *

 * Validate a DDF File against the embedded LWM2M schema.
 *

 * Support LWM2M version 1.0 and 1.1.
 */

public class DefaultDDFFileValidator implements DDFFileValidator {
    private static String LWM2M_V1_0_SCHEMA_PATH = "/schemas/LWM2M.xsd";
    private static String LWM2M_V1_1_SCHEMA_PATH = "/schemas/LWM2M-v1_1.xsd";

    private final String schema;

    /**
     * Create a {@link DDFFileValidator} using the LWM2M v1.1 schema.
     */
    public DefaultDDFFileValidator() {
        this(LwM2mVersion.V1_1);
    }

    /**
     * Create a {@link DDFFileValidator} using schema corresponding to LWM2M {@link LwM2mVersion}.
     */
    public DefaultDDFFileValidator(LwM2mVersion version) {
        Validate.notNull(version, "version must not be null");
        if (LwM2mVersion.V1_0.equals(version)) {
            schema = LWM2M_V1_0_SCHEMA_PATH;
        } else if (LwM2mVersion.V1_1.equals(version)) {
            schema = LWM2M_V1_1_SCHEMA_PATH;
        } else {
            throw new IllegalStateException(String.format("Unsupported version %s", version));
        }
    }

    @Override
    public void validate(Node xmlToValidate) throws InvalidDDFFileException {
        try {
            validate(new DOMSource(xmlToValidate));
        } catch (SAXException | IOException e) {
            throw new InvalidDDFFileException(e);
        }
    }

    /**
     * Validate a XML {@link Source} against the embedded LWM2M Schema.
     *
     * @param xmlToValidate an XML source to validate
     * @throws SAXException see {@link Validator#validate(Source)}
     * @throws IOException see {@link Validator#validate(Source)}
     */
    public void validate(Source xmlToValidate) throws SAXException, IOException {
        Validator validator = getEmbeddedLwM2mSchema().newValidator();
        validator.validate(xmlToValidate);
    }

    /**
     * Get the Embedded the LWM2M.xsd Schema.
     *
     * @throws SAXException see {@link SchemaFactory#newSchema(Source)}
     */
    protected Schema getEmbeddedLwM2mSchema() throws SAXException {
        InputStream inputStream = DDFFileValidator.class.getResourceAsStream(schema);
        Source source = new StreamSource(inputStream);
        SchemaFactory schemaFactory = SchemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI);
        return schemaFactory.newSchema(source);
    }
}

Output:
【漏洞类型】XML外部实体（XXE）攻击
【严重性】High
【漏洞摘要】这是一个路径遍历漏洞。原始代码在解析XML文件时，使用了`DocumentBuilderFactory`和`SchemaFactory`的默认配置，未对潜在的XML外部实体（XXE）攻击进行防护。XXE攻击允许攻击者通过构造恶意的XML输入来读取本地文件系统上的任意文件，甚至可能执行远程代码。
【关键代码模式】与`DocumentBuilderFactory`和`SchemaFactory`的配置相关的关键代码模式包括：
- `DocumentBuilderFactory.newInstance()`
- `SchemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI)`
- `builder.parse(inputStream)`
- `factory.newSchema(source)`
【修复方法说明】修复方法通过创建安全的`DocumentBuilderFactory`和`SchemaFactory`实例，并设置相应的防护特性来解决问题。最佳实践是启用“安全处理”特性，禁用DTD和外部实体引用，以防止XXE攻击。


Instruction:
作为 Java 安全专家，检测此代码中的安全漏洞：
## 内容1
### 文件路径：
leshan-core/src/main/java/org/eclipse/leshan/core/model/DDFFileParser.java
### 代码内容：
package org.eclipse.leshan.core.model;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;

import org.eclipse.leshan.core.model.ResourceModel.Operations;
import org.eclipse.leshan.core.model.ResourceModel.Type;
import org.eclipse.leshan.core.util.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.w3c.dom.DOMException;
import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.SAXException;

/**
 * A parser for Object DDF files.
 */
public class DDFFileParser {

    private static final Logger LOG = LoggerFactory.getLogger(DDFFileParser.class);

    private final DocumentBuilderFactory factory;
    private final DDFFileValidator ddfValidator;

    public DDFFileParser() {
        this(null);
    }

    /**
     * Build a DDFFileParser with a given {@link DDFFileValidator}.
     *
     * @param ddfValidator a {@link DDFFileValidator} or {@code null} if no validation required.
     * @since 1.1
     */
    public DDFFileParser(DDFFileValidator ddfValidator) {
        factory = DocumentBuilderFactory.newInstance();
        factory.setNamespaceAware(true);
        this.ddfValidator = ddfValidator;
    }

    /**
     * @deprecated use {@link #parseEx(File)}
     */
    @Deprecated
    public List<ObjectModel> parse(File ddfFile) {
        try (InputStream input = new FileInputStream(ddfFile)) {
            return parse(input, ddfFile.getName());
        } catch (Exception e) {
            LOG.error("Could not parse the resource definition file " + ddfFile.getName(), e);
        }
        return Collections.emptyList();
    }

    /**
     * @deprecated use {@link #parseEx(InputStream, String)}
     */
    @Deprecated
    public List<ObjectModel> parse(InputStream inputStream, String streamName) {
        streamName = streamName == null ? "" : streamName;

        LOG.debug("Parsing DDF file {}", streamName);

        try {
            // Parse XML file
            DocumentBuilder builder = factory.newDocumentBuilder();
            Document document = builder.parse(inputStream);

            // Validate XML against Schema
            if (ddfValidator != null) {
                ddfValidator.validate(document);
            }

            // Build list of ObjectModel
            ArrayList<ObjectModel> objects = new ArrayList<>();
            NodeList nodeList = document.getDocumentElement().getElementsByTagName("Object");
            for (int i = 0; i < nodeList.getLength(); i++) {
                objects.add(parseObject(nodeList.item(i), streamName, false));
            }
            return objects;
        } catch (Exception e) {
            LOG.error("Could not parse the resource definition file " + streamName, e);
        }
        return Collections.emptyList();
    }

    /**
     * Parse a DDF file.
     *
     * @throws InvalidDDFFileException if DDF file is not a valid.
     * @throws IOException see {@link FileInputStream#FileInputStream(File)} or
     *         {@link DocumentBuilder#parse(InputStream)}
     *
     * @since 1.1
     */
    public List<ObjectModel> parseEx(File ddfFile) throws InvalidDDFFileException, IOException {
        try (InputStream input = new FileInputStream(ddfFile)) {
            return parseEx(input, ddfFile.getName());
        }
    }

    /**
     * Parse a DDF file from an inputstream.
     *
     * @throws InvalidDDFFileException if DDF file is not a valid.
     * @throws IOException see {@link FileInputStream#FileInputStream(File)} or
     *         {@link DocumentBuilder#parse(InputStream)}
     *
     * @since 1.1
     */
    public List<ObjectModel> parseEx(InputStream inputStream, String streamName)
            throws InvalidDDFFileException, IOException {
        streamName = streamName == null ? "" : streamName;

        LOG.debug("Parsing DDF file {}", streamName);

        // Parse XML file
        try {
            DocumentBuilder builder = factory.newDocumentBuilder();
            Document document = builder.parse(inputStream);
            // Validate XML against Schema
            if (ddfValidator != null) {
                ddfValidator.validate(document);
            }

            // Build list of ObjectModel
            ArrayList<ObjectModel> objects = new ArrayList<>();
            NodeList nodeList = document.getDocumentElement().getElementsByTagName("Object");
            for (int i = 0; i < nodeList.getLength(); i++) {
                objects.add(parseObject(nodeList.item(i), streamName, ddfValidator != null));
            }
            return objects;
        } catch (InvalidDDFFileException | SAXException e) {
            throw new InvalidDDFFileException(e, "Invalid DDF file %s", streamName);
        } catch (ParserConfigurationException e) {
            throw new IllegalStateException("Unable to create Document Builder", e);
        }
    }

    private ObjectModel parseObject(Node object, String streamName, boolean raiseException)
            throws InvalidDDFFileException {

        Node objectType = object.getAttributes().getNamedItem("ObjectType");
        if (objectType == null || !"MODefinition".equals(objectType.getTextContent())) {
            // TODO change for v2.0 : we keep it for backward compatibility
            // test must be done only if validation is needed
            handleError(raiseException,
                    "Object element in %s MUST have a ObjectType attribute equals to 'MODefinition'.", streamName);
        }

        Integer id = null;
        String name = null;
        String description = null;
        String version = ObjectModel.DEFAULT_VERSION;
        boolean multiple = false;
        boolean mandatory = false;
        List<ResourceModel> resources = new ArrayList<>();
        String urn = null;
        String description2 = null;
        String lwm2mVersion = null;

        for (int i = 0; i < object.getChildNodes().getLength(); i++) {
            Node field = object.getChildNodes().item(i);
            if (field.getNodeType() != Node.ELEMENT_NODE)
                continue;

            switch (field.getNodeName()) {
            case "ObjectID":
                id = Integer.valueOf(field.getTextContent());
                break;
            case "Name":
                name = field.getTextContent();
                break;
            case "Description1":
                description = field.getTextContent();
                break;
            case "ObjectVersion":
                if (!StringUtils.isEmpty(field.getTextContent()))
                    version = field.getTextContent();
                break;
            case "MultipleInstances":
                if ("Multiple".equals(field.getTextContent())) {
                    multiple = true;
                } else if ("Single".equals(field.getTextContent())) {
                    multiple = false;
                } else {
                    // TODO remove for v2.0 : we keep it for backward compatibility
                    // test will be done in DDFFileValidator or ObjectModelValidatorif validation if needed
                    handleError(raiseException,
                            "Invalid Value for [MultipleInstances] field in %s. It MUST be 'Multiple' or 'Single' but it was %s.",
                            field.getTextContent(), streamName);
                    multiple = false;
                }
                break;
            case "Mandatory":
                if ("Mandatory".equals(field.getTextContent())) {
                    mandatory = true;
                } else if ("Optional".equals(field.getTextContent())) {
                    mandatory = false;
                } else {
                    // TODO remove for v2.0 : we keep it for backward compatibility
                    // test will be done in DDFFileValidator or ObjectModelValidator if validation if needed
                    handleError(raiseException,
                            "Invalid Value for [Mandatory] field in %s. It MUST be 'Mandatory' or 'Optional' but it was %s.",
                            field.getTextContent(), streamName);
                    mandatory = false;
                }
                break;
            case "Resources":
                for (int j = 0; j < field.getChildNodes().getLength(); j++) {
                    Node item = field.getChildNodes().item(j);
                    if (item.getNodeType() != Node.ELEMENT_NODE)
                        continue;

                    if (item.getNodeName().equals("Item")) {
                        resources.add(this.parseResource(item, streamName, raiseException));
                    } else {
                        // TODO remove for v2.0 : we keep it for backward compatibility
                        // test will be done in DDFFileValidator if validation if needed
                        handleError(raiseException, "Unexpected resources element [%s] in %s : it will be ignored.",
                                item.getNodeName(), streamName);
                    }
                }
                break;
            case "ObjectURN":
                urn = field.getTextContent();
                break;
            case "LWM2MVersion":
                lwm2mVersion = field.getTextContent();
                break;
            case "Description2":
                description2 = field.getTextContent();
                break;
            default:
                // TODO remove for v2.0 : we keep it for backward compatibility
                // test will be done in DDFFileValidator if validation if needed
                handleError(raiseException, "Unexpected object element [%s] in %s : it will be ignored.",
                        field.getNodeName(), streamName);
                break;
            }
        }

        return new ObjectModel(id, name, description, version, multiple, mandatory, resources, urn, lwm2mVersion,
                description2);

    }

    private ResourceModel parseResource(Node item, String streamName, boolean raiseException)
            throws DOMException, InvalidDDFFileException {

        Integer id = Integer.valueOf(item.getAttributes().getNamedItem("ID").getTextContent());
        String name = null;
        Operations operations = Operations.NONE;
        boolean multiple = false;
        boolean mandatory = false;
        Type type = null;
        String rangeEnumeration = null;
        String units = null;
        String description = null;

        for (int i = 0; i < item.getChildNodes().getLength(); i++) {
            Node field = item.getChildNodes().item(i);
            if (field.getNodeType() != Node.ELEMENT_NODE)
                continue;

            switch (field.getNodeName()) {
            case "Name":
                name = field.getTextContent();
                break;
            case "Operations":
                String strOp = field.getTextContent();
                if (strOp != null && !strOp.isEmpty()) {
                    operations = Operations.valueOf(strOp);
                }
                break;
            case "MultipleInstances":
                if ("Multiple".equals(field.getTextContent())) {
                    multiple = true;
                } else if ("Single".equals(field.getTextContent())) {
                    multiple = false;
                } else {
                    // TODO remove for v2.0 : we keep it for backward compatibility
                    // test will be done in DDFFileValidator or ObjectModelValidatorif validation if needed
                    handleError(raiseException,
                            "Invalid Value for [MultipleInstances] field in %s. It MUST be 'Multiple' or 'Single' but it was %s : We will consider it as a 'Single' value.",
                            field.getTextContent(), streamName);
                    multiple = false;
                }
                break;
            case "Mandatory":
                if ("Mandatory".equals(field.getTextContent())) {
                    mandatory = true;
                } else if ("Optional".equals(field.getTextContent())) {
                    mandatory = false;
                } else {
                    // TODO remove for v2.0 : we keep it for backward compatibility
                    // test will be done in DDFFileValidator or ObjectModelValidatorif validation if needed
                    handleError(raiseException,
                            "Invalid Value for [Mandatory] field in %s. It MUST be 'Mandatory' or 'Optional' but it was %s :s We will consider it as a 'Optional' value.",
                            field.getTextContent(), streamName);
                    mandatory = false;
                }
                break;
            case "Type":
                switch (field.getTextContent()) {
                case "String":
                    type = Type.STRING;
                    break;
                case "Integer":
                    type = Type.INTEGER;
                    break;
                case "Float":
                    type = Type.FLOAT;
                    break;
                case "Boolean":
                    type = Type.BOOLEAN;
                    break;
                case "Opaque":
                    type = Type.OPAQUE;
                    break;
                case "Time":
                    type = Type.TIME;
                    break;
                case "Objlnk":
                    type = Type.OBJLNK;
                    break;
                case "":
                    type = null;
                    break;
                default:
                    // TODO remove for v2.0 : we keep it for backward compatibility
                    // test will be done in DDFFileValidator validation if needed
                    handleError(raiseException, "Unexpected type value [%s] in %s : no type assigned",
                            field.getTextContent(), streamName);
                    break;
                }
                break;
            case "RangeEnumeration":
                rangeEnumeration = field.getTextContent();
                break;
            case "Units":
                units = field.getTextContent();
                break;
            case "Description":
                description = field.getTextContent();
                break;
            default:
                // TODO remove for v2.0 : we keep it for backward compatibility
                // test will be done in DDFFileValidator validation if needed
                handleError(raiseException, "Unexpected resource element [%s %s] in %s : it will be ignored.",
                        field.getNodeName(), field.getNodeType(), streamName);
                break;
            }
        }

        // TODO remove for v2.0 : we keep it for backward compatibility
        // test will be done in ObjetModelValidator if validation if needed
        if (!raiseException) {
            if (operations.isExecutable() && type != null) {
                LOG.warn("Model for Resource {}({}) in {} is invalid : an executable resource MUST NOT have a type({})",
                        name, id, streamName, type);
            } else if (!operations.isExecutable() && type == null) {
                LOG.warn(
                        "Model for Resource {}({}) in {} is invalid : a none executable resource MUST have a type. We will consider it as String.",
                        name, id, streamName, type);
                type = Type.STRING;
            }
        }

        return new ResourceModel(id, name, operations, multiple, mandatory, type, rangeEnumeration, units, description);
    }

    private void handleError(boolean raiseException, String Message, Object... args) throws InvalidDDFFileException {
        String msg = String.format(Message, args);
        if (raiseException) {
            throw new InvalidDDFFileException(msg);
        } else {
            LOG.warn(msg);
        }
    }
}

## 内容2
### 文件路径：
leshan-core/src/main/java/org/eclipse/leshan/core/model/DefaultDDFFileValidator.java
### 代码内容：
package org.eclipse.leshan.core.model;

import java.io.IOException;
import java.io.InputStream;

import javax.xml.XMLConstants;
import javax.xml.transform.Source;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamSource;
import javax.xml.validation.Schema;
import javax.xml.validation.SchemaFactory;
import javax.xml.validation.Validator;

import org.w3c.dom.Node;
import org.xml.sax.SAXException;

/**
 * A DDF File Validator.
 * <p>
 * Validate a DDF File against the embedded LWM2M.xsd schema.
 *
 * @since 1.1
 */

public class DefaultDDFFileValidator implements DDFFileValidator {
    private static String LWM2M_V1_SCHEMA_PATH = "/schemas/LWM2M.xsd";

    @Override
    public void validate(Node xmlToValidate) throws InvalidDDFFileException {
        try {
            validate(new DOMSource(xmlToValidate));
        } catch (SAXException | IOException e) {
            throw new InvalidDDFFileException(e);
        }
    }

    /**
     * Validate a XML {@link Source} against the embedded LWM2M.xsd Schema.
     *
     * @param xmlToValidate an XML source to validate
     * @throws SAXException see {@link Validator#validate(Source)}
     * @throws IOException see {@link Validator#validate(Source)}
     */
    public void validate(Source xmlToValidate) throws SAXException, IOException {
        Validator validator = getEmbeddedLwM2mSchema().newValidator();
        validator.validate(xmlToValidate);
    }

    /**
     * Get the Embedded the LWM2M.xsd Schema.
     *
     * @throws SAXException see {@link SchemaFactory#newSchema(Source)}
     */
    protected Schema getEmbeddedLwM2mSchema() throws SAXException {
        InputStream inputStream = DDFFileValidator.class.getResourceAsStream(LWM2M_V1_SCHEMA_PATH);
        Source source = new StreamSource(inputStream);
        SchemaFactory schemaFactory = SchemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI);
        return schemaFactory.newSchema(source);
    }
}

Output:
【漏洞类型】XML外部实体（XXE）注入
【严重性】高
【漏洞摘要】原始代码存在XML外部实体（XXE）注入漏洞。具体表现为在`DocumentBuilderFactory.newInstance()`和`SchemaFactory.newInstance()`创建XML解析器和验证器时，未禁用DTD解析和其他潜在的XXE攻击特性。这使得攻击者可以通过构造恶意的XML文件来执行外部实体注入攻击，导致资源耗尽、信息泄露等安全问题。
【关键代码模式】与`DocumentBuilderFactory`和`SchemaFactory`相关的代码行，特别是未设置安全特性的地方，例如：
```java
factory = DocumentBuilderFactory.newInstance();
factory.setNamespaceAware(true);
```
以及：
```java
SchemaFactory schemaFactory = SchemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI);
```
【修复方法说明】修复方法通过在`createDocumentBuilderFactory()`和`createSchemaFactory()`中设置安全特性来禁用DTD解析和其他XXE攻击特性，从而解决问题。这种方法遵循了OWASP的XML外部实体预防最佳实践。