Code/Projects/PacketLevelSignatureExtractor/src/main/java/edu/uci/iotproject/SignatureGenerator.java

   1 package edu.uci.iotproject;
   2
   3 import static edu.uci.iotproject.analysis.UserAction.Type;
   4
   5 import edu.uci.iotproject.analysis.*;
   6 import edu.uci.iotproject.io.PrintWriterUtils;
   7 import edu.uci.iotproject.io.TriggerTimesFileReader;
   8 import edu.uci.iotproject.trafficreassembly.layer3.Conversation;
   9 import edu.uci.iotproject.trafficreassembly.layer3.TcpReassembler;
  10 import edu.uci.iotproject.util.PcapPacketUtils;
  11 import edu.uci.iotproject.util.PrintUtils;
  12 import org.apache.commons.math3.stat.clustering.Cluster;
  13 import org.apache.commons.math3.stat.clustering.DBSCANClusterer;
  14 import org.pcap4j.core.*;
  15 import org.pcap4j.packet.namednumber.DataLinkType;
  16
  17 import java.io.*;
  18 import java.net.UnknownHostException;
  19 import java.time.Duration;
  20 import java.time.Instant;
  21 import java.util.*;
  22 import java.util.concurrent.TimeoutException;
  23 import java.util.stream.Collectors;
  24 import java.util.stream.Stream;
  25
  26 /**
  27  * This is a system that reads PCAP files to compare
  28  * patterns of DNS hostnames, packet sequences, and packet
  29  * lengths with training data to determine certain events
  30  * or actions for smart home devices.
  31  *
  32  * @author Janus Varmarken
  33  * @author Rahmadi Trimananda (rtrimana@uci.edu)
  34  * @version 0.1
  35  */
  36 public class SignatureGenerator {
  37
  38     /**
  39      * If set to {@code true}, output written to the results file is also dumped to standard out.
  40      */
  41     private static boolean DUPLICATE_OUTPUT_TO_STD_OUT = true;
  42     /**
  43      * File name for logging.
  44      */
  45     private static String LOG_EXTENSION = "_signature-generation.log";
  46     /**
  47      * Directory for logging.
  48      */
  49     private static String LOG_DIRECTORY = "./";
  50
  51     public static void main(String[] args) throws PcapNativeException, NotOpenException, EOFException,
  52             TimeoutException, UnknownHostException, IOException {
  53         // -------------------------------------------------------------------------------------------------------------
  54         // ------------ # Code for extracting traffic generated by a device within x seconds of a trigger # ------------
  55         if (args.length < 11) {
  56             String errMsg = String.format("Usage: %s inputPcapFile outputPcapFile triggerTimesFile deviceIp" +
  57                             " onSignatureFile offSignatureFile onClusterAnalysisFile offClusterAnalysisFile epsilon" +
  58                             " deletedSequencesOn deletedSequencesOff" +
  59                             "\n  inputPcapFile: the target of the detection" +
  60                             "\n  outputPcapFile: the processed PCAP file through 15-second window filtering" +
  61                             "\n  triggerTimesFile: the trigger timestamps" +
  62                             "\n  deviceIp: the IP address of the device we want to generate a signature for" +
  63                             "\n  onSignatureFile: name of the ON signature file" +
  64                             "\n  offSignatureFile: name of the OFF signature file" +
  65                             "\n  onClusterAnalysisFile: name of the ON signature cluster analysis file" +
  66                             "\n  offClusterAnalysisFile: name of the OFF signature cluster analysis file" +
  67                             "\n  epsilon: epsilon value of the DBSCAN algorithm" +
  68                             "\n  deletedSequencesOn: sequences to be deleted from the final ON signature" +
  69                             " (please separate with commas, e.g., 0,1,2, or put '-1' if not needed)" +
  70                             "\n  deletedSequencesOff: sequences to be deleted from the final OFF signature" +
  71                             " (please separate with commas, e.g., 0,1,2, or put '-1' if not needed)",
  72                     SignatureGenerator.class.getSimpleName());
  73             System.out.println(errMsg);
  74             return;
  75         }
  76         boolean verbose = true;
  77         final String inputPcapFile = args[0];
  78         final String outputPcapFile = args[1];
  79         final String triggerTimesFile = args[2];
  80         final String deviceIp = args[3];
  81         final String onSignatureFile = args[4];
  82         final String offSignatureFile = args[5];
  83         final String onClusterAnalysisFile = args[6];
  84         final String offClusterAnalysisFile = args[7];
  85         final double eps = Double.parseDouble(args[8]);
  86         final String deletedSequencesOn = args[9];
  87         final String deletedSequencesOff = args[10];
  88         final String logFile = inputPcapFile + LOG_EXTENSION;
  89
  90         // Prepare file outputter.
  91         File outputFile = new File(logFile);
  92         outputFile.getParentFile().mkdirs();
  93         final PrintWriter resultsWriter = new PrintWriter(new FileWriter(outputFile));
  94
  95         // =========================================== TRAFFIC FILTERING ============================================
  96
  97         TriggerTimesFileReader ttfr = new TriggerTimesFileReader();
  98         List<Instant> triggerTimes = ttfr.readTriggerTimes(triggerTimesFile, false);
  99         // Tag each trigger with "ON" or "OFF", assuming that the first trigger is an "ON" and that they alternate.
 100         List<UserAction> userActions = new ArrayList<>();
 101         for (int i = 0; i < triggerTimes.size(); i++) {
 102             userActions.add(new UserAction(i % 2 == 0 ? Type.TOGGLE_ON : Type.TOGGLE_OFF, triggerTimes.get(i)));
 103         }
 104         TriggerTrafficExtractor tte = new TriggerTrafficExtractor(inputPcapFile, triggerTimes, deviceIp);
 105         final PcapDumper outputter = Pcaps.openDead(DataLinkType.EN10MB, 65536).dumpOpen(outputPcapFile);
 106         DnsMap dnsMap = new DnsMap();
 107         TcpReassembler tcpReassembler = new TcpReassembler();
 108         TrafficLabeler trafficLabeler = new TrafficLabeler(userActions);
 109         tte.performExtraction(pkt -> {
 110             try {
 111                 outputter.dump(pkt);
 112             } catch (NotOpenException e) {
 113                 e.printStackTrace();
 114             }
 115         }, dnsMap, tcpReassembler, trafficLabeler);
 116         outputter.flush();
 117         outputter.close();
 118
 119         if (tte.getPacketsIncludedCount() != trafficLabeler.getTotalPacketCount()) {
 120             // Sanity/debug check
 121             throw new AssertionError(String.format("mismatch between packet count in %s and %s",
 122                     TriggerTrafficExtractor.class.getSimpleName(), TrafficLabeler.class.getSimpleName()));
 123         }
 124
 125         // Extract all conversations present in the filtered trace.
 126         List<Conversation> allConversations = tcpReassembler.getTcpConversations();
 127         // Group conversations by hostname.
 128         Map<String, List<Conversation>> convsByHostname =
 129                 TcpConversationUtils.groupConversationsByHostname(allConversations, dnsMap);
 130         PrintWriterUtils.println("Grouped conversations by hostname.", resultsWriter, DUPLICATE_OUTPUT_TO_STD_OUT);
 131         // For each hostname, count the frequencies of packet lengths exchanged with that hostname.
 132         final Map<String, Map<Integer, Integer>> pktLenFreqsByHostname = new HashMap<>();
 133         convsByHostname.forEach((host, convs) -> pktLenFreqsByHostname.put(host,
 134                 TcpConversationUtils.countPacketLengthFrequencies(convs)));
 135         PrintWriterUtils.println("Counted frequencies of packet lengths exchanged with each hostname.",
 136                 resultsWriter, DUPLICATE_OUTPUT_TO_STD_OUT);
 137         // For each hostname, count the frequencies of packet sequences (i.e., count how many
 138         // conversations exchange a sequence of packets of some specific lengths).
 139         final Map<String, Map<String, Integer>> pktSeqFreqsByHostname = new HashMap<>();
 140         convsByHostname.forEach((host, convs) -> pktSeqFreqsByHostname.put(host,
 141                 TcpConversationUtils.countPacketSequenceFrequencies(convs)));
 142         PrintWriterUtils.println("Counted frequencies of packet sequences exchanged with each hostname.",
 143                 resultsWriter, DUPLICATE_OUTPUT_TO_STD_OUT);
 144         // For each hostname, count frequencies of packet pairs exchanged
 145         // with that hostname across all conversations
 146         final Map<String, Map<String, Integer>> pktPairFreqsByHostname =
 147                 TcpConversationUtils.countPacketPairFrequenciesByHostname(allConversations, dnsMap);
 148         PrintWriterUtils.println("Counted frequencies of packet pairs per hostname.",
 149                 resultsWriter, DUPLICATE_OUTPUT_TO_STD_OUT);
 150         // For each user action, reassemble the set of TCP connections occurring shortly after
 151         final Map<UserAction, List<Conversation>> userActionToConversations =
 152                 trafficLabeler.getLabeledReassembledTcpTraffic();
 153         final Map<UserAction, Map<String, List<Conversation>>> userActionsToConvsByHostname =
 154                 trafficLabeler.getLabeledReassembledTcpTraffic(dnsMap);
 155         PrintWriterUtils.println("Reassembled TCP conversations occurring shortly after each user event.",
 156                 resultsWriter, DUPLICATE_OUTPUT_TO_STD_OUT);
 157
 158         /*
 159          * NOTE: no need to generate these more complex on/off maps that also contain mappings from hostname and
 160          * sequence identifiers as we do not care about hostnames and sequences during clustering.
 161          * We can simply use the UserAction->List<Conversation> map to generate ON/OFF groupings of conversations.
 162          */
 163         // Contains all ON events: hostname -> sequence identifier -> list of conversations with that sequence
 164         Map<String, Map<String, List<Conversation>>> ons = new HashMap<>();
 165         // Contains all OFF events: hostname -> sequence identifier -> list of conversations with that sequence
 166         Map<String, Map<String, List<Conversation>>> offs = new HashMap<>();
 167         userActionsToConvsByHostname.forEach((ua, hostnameToConvs) -> {
 168             Map<String, Map<String, List<Conversation>>> outer = ua.getType() == Type.TOGGLE_ON ? ons : offs;
 169             hostnameToConvs.forEach((host, convs) -> {
 170                 Map<String, List<Conversation>> seqsToConvs = TcpConversationUtils.
 171                         groupConversationsByPacketSequence(convs, verbose);
 172                 outer.merge(host, seqsToConvs, (oldMap, newMap) -> {
 173                     newMap.forEach((sequence, cs) -> oldMap.merge(sequence, cs, (list1, list2) -> {
 174                         list1.addAll(list2);
 175                         return list1;
 176                     }));
 177                     return oldMap;
 178                 });
 179             });
 180         });
 181
 182         // ============================================== PAIR CLUSTERING ============================================
 183         // TODO: No need to use the more convoluted on/off maps; Can simply use the UserAction->List<Conversation> map
 184         // TODO: when don't care about hostnames and sequences (see comment earlier).
 185         // ===========================================================================================================
 186         List<Conversation> onConversations = userActionToConversations.entrySet().stream().
 187                 filter(e -> e.getKey().getType() == Type.TOGGLE_ON). // drop all OFF events from stream
 188                 map(e -> e.getValue()). // no longer interested in the UserActions
 189                 flatMap(List::stream). // flatten List<List<T>> to a List<T>
 190                 collect(Collectors.toList());
 191         List<Conversation> offConversations = userActionToConversations.entrySet().stream().
 192                 filter(e -> e.getKey().getType() == Type.TOGGLE_OFF).
 193                 map(e -> e.getValue()).
 194                 flatMap(List::stream).
 195                 collect(Collectors.toList());
 196         //Collections.sort(onConversations, (c1, c2) -> c1.getPackets().)
 197
 198         List<PcapPacketPair> onPairs = onConversations.stream().
 199                 map(c -> c.isTls() ? TcpConversationUtils.extractTlsAppDataPacketPairs(c) :
 200                         TcpConversationUtils.extractPacketPairs(c)).
 201                 flatMap(List::stream). // flatten List<List<>> to List<>
 202                 collect(Collectors.toList());
 203         List<PcapPacketPair> offPairs = offConversations.stream().
 204                 map(c -> c.isTls() ? TcpConversationUtils.extractTlsAppDataPacketPairs(c) :
 205                         TcpConversationUtils.extractPacketPairs(c)).
 206                 flatMap(List::stream). // flatten List<List<>> to List<>
 207                 collect(Collectors.toList());
 208         // Note: need to update the DnsMap of all PcapPacketPairs if we want to use the IP/hostname-sensitive distance.
 209         Stream.concat(Stream.of(onPairs), Stream.of(offPairs)).flatMap(List::stream).forEach(p -> p.setDnsMap(dnsMap));
 210         // Perform clustering on conversation logged as part of all ON events.
 211         // Calculate number of events per type (only ON/only OFF), which means half of the number of all timestamps.
 212         int numberOfEventsPerType = triggerTimes.size() / 2;
 213         int lowerBound = numberOfEventsPerType - (int)(numberOfEventsPerType * 0.1);
 214         int upperBound = numberOfEventsPerType + (int)(numberOfEventsPerType * 0.1);
 215         int minPts = lowerBound;
 216         DBSCANClusterer<PcapPacketPair> onClusterer = new DBSCANClusterer<>(eps, minPts);
 217         List<Cluster<PcapPacketPair>> onClusters = onClusterer.cluster(onPairs);
 218         // Perform clustering on conversation logged as part of all OFF events.
 219         DBSCANClusterer<PcapPacketPair> offClusterer = new DBSCANClusterer<>(eps, minPts);
 220         List<Cluster<PcapPacketPair>> offClusters = offClusterer.cluster(offPairs);
 221         // Sort the conversations as reference
 222         List<Conversation> sortedAllConversation = TcpConversationUtils.sortConversationList(allConversations);
 223         // Output clusters
 224         PrintWriterUtils.println("========================================", resultsWriter,
 225                 DUPLICATE_OUTPUT_TO_STD_OUT);
 226         PrintWriterUtils.println("       Clustering results for ON        ", resultsWriter,
 227                 DUPLICATE_OUTPUT_TO_STD_OUT);
 228         PrintWriterUtils.println("       Number of clusters: " + onClusters.size(), resultsWriter,
 229                 DUPLICATE_OUTPUT_TO_STD_OUT);
 230         int count = 0;
 231         List<List<List<PcapPacket>>> ppListOfListReadOn = new ArrayList<>();
 232         List<List<List<PcapPacket>>> ppListOfListListOn = new ArrayList<>();
 233         List<List<List<PcapPacket>>> corePointRangeSignatureOn = new ArrayList<>();
 234         for (Cluster<PcapPacketPair> c : onClusters) {
 235             PrintWriterUtils.println(String.format("<<< Cluster #%02d (%03d points) >>>", ++count, c.getPoints().size()),
 236                     resultsWriter, DUPLICATE_OUTPUT_TO_STD_OUT);
 237             PrintWriterUtils.println(PrintUtils.toSummaryString(c), resultsWriter, DUPLICATE_OUTPUT_TO_STD_OUT);
 238             if(c.getPoints().size() > lowerBound && c.getPoints().size() < upperBound) {
 239                 // Print to file
 240                 List<List<PcapPacket>> ppListOfList = PcapPacketUtils.clusterToListOfPcapPackets(c);
 241                 // Check for overlaps and decide whether to do range-based or conservative checking
 242                 corePointRangeSignatureOn.add(PcapPacketUtils.extractRangeCorePoints(ppListOfList, eps, minPts));
 243                 ppListOfListListOn.add(ppListOfList);
 244             }
 245         }
 246         PrintWriterUtils.println("========================================", resultsWriter,
 247                 DUPLICATE_OUTPUT_TO_STD_OUT);
 248         PrintWriterUtils.println("       Clustering results for OFF        ", resultsWriter,
 249                 DUPLICATE_OUTPUT_TO_STD_OUT);
 250         PrintWriterUtils.println("       Number of clusters: " + offClusters.size(), resultsWriter,
 251                 DUPLICATE_OUTPUT_TO_STD_OUT);
 252         count = 0;
 253         List<List<List<PcapPacket>>> ppListOfListReadOff = new ArrayList<>();
 254         List<List<List<PcapPacket>>> ppListOfListListOff = new ArrayList<>();
 255         List<List<List<PcapPacket>>> corePointRangeSignatureOff = new ArrayList<>();
 256         for (Cluster<PcapPacketPair> c : offClusters) {
 257             PrintWriterUtils.println(String.format("<<< Cluster #%03d (%06d points) >>>", ++count, c.getPoints().size()),
 258                     resultsWriter, DUPLICATE_OUTPUT_TO_STD_OUT);
 259             PrintWriterUtils.println(PrintUtils.toSummaryString(c), resultsWriter, DUPLICATE_OUTPUT_TO_STD_OUT);
 260             if(c.getPoints().size() > lowerBound && c.getPoints().size() < upperBound) {
 261                 // Print to file
 262                 List<List<PcapPacket>> ppListOfList = PcapPacketUtils.clusterToListOfPcapPackets(c);
 263                 // Check for overlaps and decide whether to do range-based or conservative checking
 264                 corePointRangeSignatureOff.add(PcapPacketUtils.extractRangeCorePoints(ppListOfList, eps, minPts));
 265                 ppListOfListListOff.add(ppListOfList);
 266             }
 267         }
 268
 269         // =========================================== SIGNATURE CREATION ===========================================
 270         // Concatenate
 271         ppListOfListListOn = PcapPacketUtils.concatSequences(ppListOfListListOn, sortedAllConversation);
 272         // Remove sequences in the list that have overlap
 273         StringTokenizer stringTokenizerOn = new StringTokenizer(deletedSequencesOn, ",");
 274         while(stringTokenizerOn.hasMoreTokens()) {
 275             int sequenceToDelete = Integer.parseInt(stringTokenizerOn.nextToken());
 276             if (sequenceToDelete == -1) { // '-1' means there is no removal
 277                 break;
 278             }
 279             PcapPacketUtils.removeSequenceFromSignature(ppListOfListListOn, sequenceToDelete);
 280         }
 281         ppListOfListListOn = PcapPacketUtils.sortSequences(ppListOfListListOn);
 282
 283         // Concatenate
 284         ppListOfListListOff = PcapPacketUtils.concatSequences(ppListOfListListOff, sortedAllConversation);
 285         // Remove sequences in the list that have overlap
 286         StringTokenizer stringTokenizerOff = new StringTokenizer(deletedSequencesOff, ",");
 287         while(stringTokenizerOff.hasMoreTokens()) {
 288             int sequenceToDelete = Integer.parseInt(stringTokenizerOff.nextToken());
 289             if (sequenceToDelete == -1) { // '-1' means there is no removal
 290                 break;
 291             }
 292             PcapPacketUtils.removeSequenceFromSignature(ppListOfListListOff, sequenceToDelete);
 293         }
 294         ppListOfListListOff = PcapPacketUtils.sortSequences(ppListOfListListOff);
 295         // Write the signatures into the screen
 296         PrintWriterUtils.println("========================================", resultsWriter,
 297                 DUPLICATE_OUTPUT_TO_STD_OUT);
 298         PrintWriterUtils.println("              ON Signature              ", resultsWriter,
 299                 DUPLICATE_OUTPUT_TO_STD_OUT);
 300         PrintWriterUtils.println("========================================", resultsWriter,
 301                 DUPLICATE_OUTPUT_TO_STD_OUT);
 302         PcapPacketUtils.printSignatures(ppListOfListListOn, resultsWriter, DUPLICATE_OUTPUT_TO_STD_OUT);
 303         PrintWriterUtils.println("========================================", resultsWriter,
 304                 DUPLICATE_OUTPUT_TO_STD_OUT);
 305         PrintWriterUtils.println("              OFF Signature             ", resultsWriter,
 306                 DUPLICATE_OUTPUT_TO_STD_OUT);
 307         PrintWriterUtils.println("========================================", resultsWriter,
 308                 DUPLICATE_OUTPUT_TO_STD_OUT);
 309         PcapPacketUtils.printSignatures(ppListOfListListOff, resultsWriter, DUPLICATE_OUTPUT_TO_STD_OUT);
 310         // Printing signatures into files
 311         PrintUtils.serializeIntoFile(onSignatureFile, ppListOfListListOn);
 312         PrintUtils.serializeIntoFile(offSignatureFile, ppListOfListListOff);
 313         // Printing cluster analyses into files
 314         PrintUtils.serializeIntoFile(onClusterAnalysisFile, corePointRangeSignatureOn);
 315         PrintUtils.serializeIntoFile(offClusterAnalysisFile, corePointRangeSignatureOff);
 316
 317         // =========================================== SIGNATURE DURATION ===========================================
 318         List<Instant> firstSignatureTimestamps = new ArrayList<>();
 319         List<Instant> lastSignatureTimestamps = new ArrayList<>();
 320         if (!ppListOfListListOn.isEmpty()) {
 321             List<List<PcapPacket>> firstListOnSign = ppListOfListListOn.get(0);
 322             List<List<PcapPacket>> lastListOnSign = ppListOfListListOn.get(ppListOfListListOn.size() - 1);
 323             // Load ON signature first and last packet's timestamps
 324             for (List<PcapPacket> list : firstListOnSign) {
 325                 // Get timestamp Instant from the last packet
 326                 firstSignatureTimestamps.add(list.get(0).getTimestamp());
 327             }
 328             for (List<PcapPacket> list : lastListOnSign) {
 329                 // Get timestamp Instant from the last packet
 330                 int lastPacketIndex = list.size() - 1;
 331                 lastSignatureTimestamps.add(list.get(lastPacketIndex).getTimestamp());
 332             }
 333         }
 334
 335         if (!ppListOfListListOn.isEmpty()) {
 336             List<List<PcapPacket>> firstListOffSign = ppListOfListListOff.get(0);
 337             List<List<PcapPacket>> lastListOffSign = ppListOfListListOff.get(ppListOfListListOff.size() - 1);
 338             // Load OFF signature first and last packet's timestamps
 339             for (List<PcapPacket> list : firstListOffSign) {
 340                 // Get timestamp Instant from the last packet
 341                 firstSignatureTimestamps.add(list.get(0).getTimestamp());
 342             }
 343             for (List<PcapPacket> list : lastListOffSign) {
 344                 // Get timestamp Instant from the last packet
 345                 int lastPacketIndex = list.size() - 1;
 346                 lastSignatureTimestamps.add(list.get(lastPacketIndex).getTimestamp());
 347             }
 348         }
 349         // Sort the timestamps
 350         firstSignatureTimestamps.sort((p1, p2) -> {
 351             return p1.compareTo(p2);
 352         });
 353         // Sort the timestamps
 354         lastSignatureTimestamps.sort((p1, p2) -> {
 355             return p1.compareTo(p2);
 356         });
 357
 358         Iterator<Instant> iterFirst = firstSignatureTimestamps.iterator();
 359         Iterator<Instant> iterLast = lastSignatureTimestamps.iterator();
 360         long duration;
 361         long maxDuration = Long.MIN_VALUE;
 362         PrintWriterUtils.println("========================================", resultsWriter,
 363                 DUPLICATE_OUTPUT_TO_STD_OUT);
 364         PrintWriterUtils.println("           Signature Durations          ", resultsWriter,
 365                 DUPLICATE_OUTPUT_TO_STD_OUT);
 366         PrintWriterUtils.println("========================================", resultsWriter,
 367                 DUPLICATE_OUTPUT_TO_STD_OUT);
 368         while (iterFirst.hasNext() && iterLast.hasNext()) {
 369             Instant firstInst = (Instant) iterFirst.next();
 370             Instant lastInst = (Instant) iterLast.next();
 371             Duration dur = Duration.between(firstInst, lastInst);
 372             duration = dur.toMillis();
 373             // Check duration --- should be below 15 seconds
 374             if (duration > TriggerTrafficExtractor.INCLUSION_WINDOW_MILLIS) {
 375                 while (duration > TriggerTrafficExtractor.INCLUSION_WINDOW_MILLIS && iterFirst.hasNext()) {
 376                     // that means we have to move to the next trigger
 377                     firstInst = (Instant) iterFirst.next();
 378                     dur = Duration.between(firstInst, lastInst);
 379                     duration = dur.toMillis();
 380                 }
 381             } else { // Below 0/Negative --- that means we have to move to the next signature
 382                 while (duration < 0 && iterLast.hasNext()) {
 383                     // that means we have to move to the next trigger
 384                     lastInst = (Instant) iterLast.next();
 385                     dur = Duration.between(firstInst, lastInst);
 386                     duration = dur.toMillis();
 387                 }
 388             }
 389             PrintWriterUtils.println(duration, resultsWriter, DUPLICATE_OUTPUT_TO_STD_OUT);
 390             // Update duration if this bigger than the max value and still less than the window inclusion time
 391             maxDuration = maxDuration < duration && duration <= TriggerTrafficExtractor.INCLUSION_WINDOW_MILLIS ?
 392                     duration : maxDuration;
 393         }
 394         // Just assign the value 0 if there is no signature
 395         if (maxDuration == Long.MIN_VALUE) {
 396             maxDuration = 0;
 397         }
 398         PrintWriterUtils.println("========================================", resultsWriter,
 399                 DUPLICATE_OUTPUT_TO_STD_OUT);
 400         PrintWriterUtils.println("Max signature duration: " + maxDuration, resultsWriter,
 401                 DUPLICATE_OUTPUT_TO_STD_OUT);
 402         PrintWriterUtils.println("========================================", resultsWriter,
 403                 DUPLICATE_OUTPUT_TO_STD_OUT);
 404         resultsWriter.flush();
 405         resultsWriter.close();
 406         // ==========================================================================================================
 407     }
 408 }