1 package edu.uci.iotproject.detection.layer2;
3 import edu.uci.iotproject.analysis.TriggerTrafficExtractor;
4 import edu.uci.iotproject.analysis.UserAction;
5 import edu.uci.iotproject.detection.AbstractClusterMatcher;
6 import edu.uci.iotproject.detection.ClusterMatcherObserver;
7 import edu.uci.iotproject.detection.SignatureDetectorObserver;
8 import edu.uci.iotproject.io.PcapHandleReader;
9 import edu.uci.iotproject.io.PrintWriterUtils;
10 import edu.uci.iotproject.trafficreassembly.layer2.Layer2Flow;
11 import edu.uci.iotproject.trafficreassembly.layer2.Layer2FlowReassembler;
12 import edu.uci.iotproject.util.PcapPacketUtils;
13 import edu.uci.iotproject.util.PrintUtils;
14 import org.jgrapht.GraphPath;
15 import org.jgrapht.alg.shortestpath.DijkstraShortestPath;
16 import org.jgrapht.graph.DefaultWeightedEdge;
17 import org.jgrapht.graph.SimpleDirectedWeightedGraph;
18 import org.pcap4j.core.*;
21 import java.io.FileWriter;
22 import java.io.IOException;
23 import java.io.PrintWriter;
24 import java.time.Duration;
26 import java.util.function.Function;
27 import java.util.regex.Pattern;
30 * Performs layer 2 signature detection.
32 * @author Janus Varmarken {@literal <jvarmark@uci.edu>}
33 * @author Rahmadi Trimananda {@literal <rtrimana@uci.edu>}
35 public class Layer2SignatureDetector implements PacketListener, ClusterMatcherObserver {
38 * If set to {@code true}, output written to the results file is also dumped to standard out.
40 private static boolean DUPLICATE_OUTPUT_TO_STD_OUT = true;
42 private static List<Function<Layer2Flow, Boolean>> parseSignatureMacFilters(String filtersString) {
43 List<Function<Layer2Flow, Boolean>> filters = new ArrayList<>();
44 String[] filterRegexes = filtersString.split(";");
45 for (String filterRegex : filterRegexes) {
46 final Pattern regex = Pattern.compile(filterRegex);
47 // Create a filter that includes all flows where one of the two MAC addresses match the regex.
48 filters.add(flow -> regex.matcher(flow.getEndpoint1().toString()).matches() || regex.matcher(flow.getEndpoint2().toString()).matches());
53 public static void main(String[] args) throws PcapNativeException, NotOpenException, IOException {
54 // Parse required parameters.
55 if (args.length < 10) {
56 String errMsg = String.format("SPECTO version 1.0\n" +
57 "Copyright (C) 2018-2019 Janus Varmarken and Rahmadi Trimananda.\n" +
58 "University of California, Irvine.\n" +
59 "All rights reserved.\n\n" +
60 "Usage: %s inputPcapFile onAnalysisFile offAnalysisFile onSignatureFile offSignatureFile " +
61 "resultsFile signatureDuration eps onMaxSkippedPackets offMaxSkippedPackets" +
62 "\n inputPcapFile: the target of the detection" +
63 "\n onAnalysisFile: the file that contains the ON clusters analysis" +
64 "\n offAnalysisFile: the file that contains the OFF clusters analysis" +
65 "\n onSignatureFile: the file that contains the ON signature to search for" +
66 "\n offSignatureFile: the file that contains the OFF signature to search for" +
67 "\n resultsFile: where to write the results of the detection" +
68 "\n signatureDuration: the maximum duration of signature detection" +
69 "\n eps: the epsilon value for the DBSCAN algorithm" +
70 "\n onMaxSkippedPackets: the maximum duration of ON signature detection (put -1 if not used)" +
71 "\n offMaxSkippedPackets: the maximum duration of OFF signature detection (put -1 if not used)",
72 Layer2SignatureDetector.class.getSimpleName());
73 System.out.println(errMsg);
74 String optParamsExplained = "Above are the required, positional arguments. In addition to these, the " +
75 "following options and associated positional arguments may be used:\n" +
76 " '-onmacfilters <regex>;<regex>;...;<regex>' which specifies that sequence matching should ONLY" +
77 " be performed on flows where the MAC of one of the two endpoints matches the given regex. Note " +
78 "that you MUST specify a regex for each cluster of the signature. This is to facilitate more " +
79 "aggressive filtering on parts of the signature (e.g., the communication that involves the " +
80 "smart home device itself as one can drop all flows that do not include an endpoint with a MAC " +
81 "that matches the vendor's prefix).\n" +
82 " '-offmacfilters <regex>;<regex>;...;<regex>' works exactly the same as onmacfilters, but " +
83 "applies to the OFF signature instead of the ON signature.\n" +
84 " '-sout <boolean literal>' true/false literal indicating if output should also be printed to std out; default is true.";
85 System.out.println(optParamsExplained);
88 final String pcapFile = args[0];
89 final String onClusterAnalysisFile = args[1];
90 final String offClusterAnalysisFile = args[2];
91 final String onSignatureFile = args[3];
92 final String offSignatureFile = args[4];
93 final String resultsFile = args[5];
94 final int signatureDuration = Integer.parseInt(args[6]);
95 final double eps = Double.parseDouble(args[7]);
96 final int onMaxSkippedPackets = Integer.parseInt(args[8]);
97 final int offMaxSkippedPackets = Integer.parseInt(args[8]);
99 // Parse optional parameters.
100 List<Function<Layer2Flow, Boolean>> onSignatureMacFilters = null, offSignatureMacFilters = null;
101 final int optParamsStartIdx = 7;
102 if (args.length > optParamsStartIdx) {
103 for (int i = optParamsStartIdx; i < args.length; i++) {
104 if (args[i].equalsIgnoreCase("-onMacFilters")) {
105 // Next argument is the cluster-wise MAC filters (separated by semicolons).
106 onSignatureMacFilters = parseSignatureMacFilters(args[i+1]);
107 } else if (args[i].equalsIgnoreCase("-offMacFilters")) {
108 // Next argument is the cluster-wise MAC filters (separated by semicolons).
109 offSignatureMacFilters = parseSignatureMacFilters(args[i+1]);
110 } else if (args[i].equalsIgnoreCase("-sout")) {
111 // Next argument is a boolean true/false literal.
112 DUPLICATE_OUTPUT_TO_STD_OUT = Boolean.parseBoolean(args[i+1]);
117 // Prepare file outputter.
118 File outputFile = new File(resultsFile);
119 outputFile.getParentFile().mkdirs();
120 final PrintWriter resultsWriter = new PrintWriter(new FileWriter(outputFile));
121 // Include metadata as comments at the top
122 PrintWriterUtils.println("# Detection results for:", resultsWriter, DUPLICATE_OUTPUT_TO_STD_OUT);
123 PrintWriterUtils.println("# - inputPcapFile: " + pcapFile, resultsWriter, DUPLICATE_OUTPUT_TO_STD_OUT);
124 PrintWriterUtils.println("# - onAnalysisFile: " + onClusterAnalysisFile, resultsWriter, DUPLICATE_OUTPUT_TO_STD_OUT);
125 PrintWriterUtils.println("# - offAnalysisFile: " + offClusterAnalysisFile, resultsWriter, DUPLICATE_OUTPUT_TO_STD_OUT);
126 PrintWriterUtils.println("# - onSignatureFile: " + onSignatureFile, resultsWriter, DUPLICATE_OUTPUT_TO_STD_OUT);
127 PrintWriterUtils.println("# - offSignatureFile: " + offSignatureFile, resultsWriter, DUPLICATE_OUTPUT_TO_STD_OUT);
128 resultsWriter.flush();
130 // Create signature detectors and add observers that output their detected events.
131 List<List<List<PcapPacket>>> onSignature = PrintUtils.deserializeFromFile(onSignatureFile);
132 List<List<List<PcapPacket>>> offSignature = PrintUtils.deserializeFromFile(offSignatureFile);
133 // Load signature analyses
134 List<List<List<PcapPacket>>> onClusterAnalysis = PrintUtils.deserializeFromFile(onClusterAnalysisFile);
135 List<List<List<PcapPacket>>> offClusterAnalysis = PrintUtils.deserializeFromFile(offClusterAnalysisFile);
136 // TODO: FOR NOW WE DECIDE PER SIGNATURE AND THEN WE OR THE BOOLEANS
137 // TODO: SINCE WE ONLY HAVE 2 SIGNATURES FOR NOW (ON AND OFF), THEN IT IS USUALLY EITHER RANGE-BASED OR
138 // TODO: STRICT MATCHING
139 // Check if we should use range-based matching
140 boolean isRangeBasedForOn = PcapPacketUtils.isRangeBasedMatching(onSignature, eps, offSignature);
141 boolean isRangeBasedForOff = PcapPacketUtils.isRangeBasedMatching(offSignature, eps, onSignature);
142 // TODO: WE DON'T DO RANGE-BASED FOR NOW BECAUSE THE RESULTS ARE TERRIBLE FOR LAYER 2 MATCHING
143 // TODO: THIS WOULD ONLY WORK FOR SIGNATURES LONGER THAN 2 PACKETS
144 // boolean isRangeBasedForOn = false;
145 // boolean isRangeBasedForOff = false;
146 // Update the signature with ranges if it is range-based
147 if (isRangeBasedForOn) {
148 onSignature = PcapPacketUtils.useRangeBasedMatching(onSignature, onClusterAnalysis);
150 if (isRangeBasedForOff) {
151 offSignature = PcapPacketUtils.useRangeBasedMatching(offSignature, offClusterAnalysis);
153 Layer2SignatureDetector onDetector = onSignatureMacFilters == null ?
154 new Layer2SignatureDetector(onSignature, signatureDuration, isRangeBasedForOn, eps, onMaxSkippedPackets) :
155 new Layer2SignatureDetector(onSignature, onSignatureMacFilters, signatureDuration,
156 isRangeBasedForOn, eps, onMaxSkippedPackets);
157 Layer2SignatureDetector offDetector = offSignatureMacFilters == null ?
158 new Layer2SignatureDetector(offSignature, signatureDuration, isRangeBasedForOff, eps, offMaxSkippedPackets) :
159 new Layer2SignatureDetector(offSignature, offSignatureMacFilters, signatureDuration,
160 isRangeBasedForOff, eps, offMaxSkippedPackets);
161 final List<UserAction> detectedEvents = new ArrayList<>();
162 onDetector.addObserver((signature, match) -> {
163 UserAction event = new UserAction(UserAction.Type.TOGGLE_ON, match.get(0).get(0).getTimestamp());
164 PrintWriterUtils.println(event, resultsWriter, DUPLICATE_OUTPUT_TO_STD_OUT);
165 detectedEvents.add(event);
167 offDetector.addObserver((signature, match) -> {
168 UserAction event = new UserAction(UserAction.Type.TOGGLE_OFF, match.get(0).get(0).getTimestamp());
169 PrintWriterUtils.println(event, resultsWriter, DUPLICATE_OUTPUT_TO_STD_OUT);
170 detectedEvents.add(event);
173 // Load the PCAP file
176 handle = Pcaps.openOffline(pcapFile, PcapHandle.TimestampPrecision.NANO);
177 } catch (PcapNativeException pne) {
178 handle = Pcaps.openOffline(pcapFile);
180 PcapHandleReader reader = new PcapHandleReader(handle, p -> true, onDetector, offDetector);
182 reader.readFromHandle();
184 String resultOn = "# Number of detected events of type " + UserAction.Type.TOGGLE_ON + ": " +
185 detectedEvents.stream().filter(ua -> ua.getType() == UserAction.Type.TOGGLE_ON).count();
186 String resultOff = "# Number of detected events of type " + UserAction.Type.TOGGLE_OFF + ": " +
187 detectedEvents.stream().filter(ua -> ua.getType() == UserAction.Type.TOGGLE_OFF).count();
188 String onMaximumSkippedPackets = "# Maximum number of skipped packets in ON signature " +
189 Integer.toString(onDetector.getMaxSkippedPackets());
190 // String onMaxSkippedPackets = "# Number of skipped packets in ON signature: ";
191 // for(Integer skippedPackets : onDetector.getMaxSkippedPackets()) {
192 // System.out.println(skippedPackets);
194 String offMaximumSkippedPackets = "# Maximum number of skipped packets in OFF signature " +
195 Integer.toString(offDetector.getMaxSkippedPackets());
196 // String offMaxSkippedPackets = "# Number of skipped packets in OFF signature: ";
197 // for(Integer skippedPackets : offDetector.getMaxSkippedPackets()) {
198 // System.out.println(skippedPackets);
200 PrintWriterUtils.println(resultOn, resultsWriter, DUPLICATE_OUTPUT_TO_STD_OUT);
201 PrintWriterUtils.println(resultOff, resultsWriter, DUPLICATE_OUTPUT_TO_STD_OUT);
202 PrintWriterUtils.println(onMaximumSkippedPackets, resultsWriter, DUPLICATE_OUTPUT_TO_STD_OUT);
203 PrintWriterUtils.println(offMaximumSkippedPackets, resultsWriter, DUPLICATE_OUTPUT_TO_STD_OUT);
205 // Flush output to results file and close it.
206 resultsWriter.flush();
207 resultsWriter.close();
211 * The signature that this {@link Layer2SignatureDetector} is searching for.
213 private final List<List<List<PcapPacket>>> mSignature;
216 * The {@link Layer2ClusterMatcher}s in charge of detecting each individual sequence of packets that together make
217 * up the the signature.
219 private final List<Layer2ClusterMatcher> mClusterMatchers;
222 * For each {@code i} ({@code i >= 0 && i < mPendingMatches.length}), {@code mPendingMatches[i]} holds the matches
223 * found by the {@link Layer2ClusterMatcher} at {@code mClusterMatchers.get(i)} that have yet to be "consumed",
224 * i.e., have yet to be included in a signature detected by this {@link Layer2SignatureDetector} (a signature can
225 * be encompassed of multiple packet sequences occurring shortly after one another on multiple connections).
227 private final List<List<PcapPacket>>[] mPendingMatches;
230 * Maps a {@link Layer2ClusterMatcher} to its corresponding index in {@link #mPendingMatches}.
232 private final Map<Layer2ClusterMatcher, Integer> mClusterMatcherIds;
235 * In charge of reassembling layer 2 packet flows.
237 private final Layer2FlowReassembler mFlowReassembler = new Layer2FlowReassembler();
239 private final List<SignatureDetectorObserver> mObservers = new ArrayList<>();
241 private int mInclusionTimeMillis;
243 private int mMaxSkippedPackets;
244 // private List<Integer> mMaxSkippedPackets;
246 public Layer2SignatureDetector(List<List<List<PcapPacket>>> searchedSignature, int signatureDuration,
247 boolean isRangeBased, double eps, int limitSkippedPackets) {
248 this(searchedSignature, null, signatureDuration, isRangeBased, eps, limitSkippedPackets);
251 public Layer2SignatureDetector(List<List<List<PcapPacket>>> searchedSignature, List<Function<Layer2Flow,
252 Boolean>> flowFilters, int inclusionTimeMillis, boolean isRangeBased, double eps, int limitSkippedPackets) {
253 if (flowFilters != null && flowFilters.size() != searchedSignature.size()) {
254 throw new IllegalArgumentException("If flow filters are used, there must be a flow filter for each cluster " +
255 "of the signature.");
257 mSignature = Collections.unmodifiableList(searchedSignature);
258 List<Layer2ClusterMatcher> clusterMatchers = new ArrayList<>();
259 for (int i = 0; i < mSignature.size(); i++) {
260 List<List<PcapPacket>> cluster = mSignature.get(i);
261 Layer2ClusterMatcher clusterMatcher = flowFilters == null ?
262 new Layer2ClusterMatcher(cluster, inclusionTimeMillis, isRangeBased, eps, limitSkippedPackets) :
263 new Layer2ClusterMatcher(cluster, flowFilters.get(i), inclusionTimeMillis, isRangeBased,
264 eps, limitSkippedPackets);
265 clusterMatcher.addObserver(this);
266 clusterMatchers.add(clusterMatcher);
268 mClusterMatchers = Collections.unmodifiableList(clusterMatchers);
269 mPendingMatches = new List[mClusterMatchers.size()];
270 for (int i = 0; i < mPendingMatches.length; i++) {
271 mPendingMatches[i] = new ArrayList<>();
273 Map<Layer2ClusterMatcher, Integer> clusterMatcherIds = new HashMap<>();
274 for (int i = 0; i < mClusterMatchers.size(); i++) {
275 clusterMatcherIds.put(mClusterMatchers.get(i), i);
277 mClusterMatcherIds = Collections.unmodifiableMap(clusterMatcherIds);
278 // Register all cluster matchers to receive a notification whenever a new flow is encountered.
279 mClusterMatchers.forEach(cm -> mFlowReassembler.addObserver(cm));
280 mInclusionTimeMillis =
281 inclusionTimeMillis == 0 ? TriggerTrafficExtractor.INCLUSION_WINDOW_MILLIS : inclusionTimeMillis;
282 mMaxSkippedPackets = 0;
283 // mMaxSkippedPackets = new ArrayList<>();
286 public int getMaxSkippedPackets() {
287 return mMaxSkippedPackets;
289 // public List<Integer> getMaxSkippedPackets() {
290 // return mMaxSkippedPackets;
294 public void gotPacket(PcapPacket packet) {
295 // Forward packet processing to the flow reassembler that in turn notifies the cluster matchers as appropriate
296 mFlowReassembler.gotPacket(packet);
300 public void onMatch(AbstractClusterMatcher clusterMatcher, List<PcapPacket> match) {
301 // TODO: a cluster matcher found a match
302 if (clusterMatcher instanceof Layer2ClusterMatcher) {
303 // Add the match at the corresponding index
304 mPendingMatches[mClusterMatcherIds.get(clusterMatcher)].add(match);
305 checkSignatureMatch();
306 // Update maximum number of skipped packets
307 if (mMaxSkippedPackets < ((Layer2ClusterMatcher) clusterMatcher).getMaxSkippedPackets()) {
308 mMaxSkippedPackets = ((Layer2ClusterMatcher) clusterMatcher).getMaxSkippedPackets();
310 // mMaxSkippedPackets = ((Layer2ClusterMatcher) clusterMatcher).getMaxSkippedPackets();
314 public void addObserver(SignatureDetectorObserver observer) {
315 mObservers.add(observer);
318 public boolean removeObserver(SignatureDetectorObserver observer) {
319 return mObservers.remove(observer);
323 @SuppressWarnings("Duplicates")
324 private void checkSignatureMatch() {
325 // << Graph-based approach using Balint's idea. >>
326 // This implementation assumes that the packets in the inner lists (the sequences) are ordered by asc timestamp.
328 // There cannot be a signature match until each Layer3ClusterMatcher has found a match of its respective sequence.
329 if (Arrays.stream(mPendingMatches).noneMatch(l -> l.isEmpty())) {
331 final SimpleDirectedWeightedGraph<Vertex, DefaultWeightedEdge> graph =
332 new SimpleDirectedWeightedGraph<>(DefaultWeightedEdge.class);
333 // Add a vertex for each match found by all cluster matchers.
334 // And maintain an array to keep track of what cluster matcher each vertex corresponds to
335 final List<Vertex>[] vertices = new List[mPendingMatches.length];
336 for (int i = 0; i < mPendingMatches.length; i++) {
337 vertices[i] = new ArrayList<>();
338 for (List<PcapPacket> sequence : mPendingMatches[i]) {
339 Vertex v = new Vertex(sequence);
340 vertices[i].add(v); // retain reference for later when we are to add edges
341 graph.addVertex(v); // add to vertex to graph
344 // Add dummy source and sink vertices to facilitate search.
345 final Vertex source = new Vertex(null);
346 final Vertex sink = new Vertex(null);
347 graph.addVertex(source);
348 graph.addVertex(sink);
349 // The source is connected to all vertices that wrap the sequences detected by cluster matcher at index 0.
350 // Note: zero cost edges as this is just a dummy link to facilitate search from a common start node.
351 for (Vertex v : vertices[0]) {
352 DefaultWeightedEdge edge = graph.addEdge(source, v);
353 graph.setEdgeWeight(edge, 0.0);
355 // Similarly, all vertices that wrap the sequences detected by the last cluster matcher of the signature
356 // are connected to the sink node.
357 for (Vertex v : vertices[vertices.length-1]) {
358 DefaultWeightedEdge edge = graph.addEdge(v, sink);
359 graph.setEdgeWeight(edge, 0.0);
361 // Now link sequences detected by the cluster matcher at index i to sequences detected by the cluster
362 // matcher at index i+1 if they obey the timestamp constraint (i.e., that the latter is later in time than
364 for (int i = 0; i < vertices.length; i++) {
366 if (j < vertices.length) {
367 for (Vertex iv : vertices[i]) {
368 PcapPacket ivLast = iv.sequence.get(iv.sequence.size()-1);
369 for (Vertex jv : vertices[j]) {
370 PcapPacket jvFirst = jv.sequence.get(jv.sequence.size()-1);
371 if (ivLast.getTimestamp().isBefore(jvFirst.getTimestamp())) {
372 DefaultWeightedEdge edge = graph.addEdge(iv, jv);
373 // The weight is the duration of the i'th sequence plus the duration between the i'th
374 // and i+1'th sequence.
375 Duration d = Duration.
376 between(iv.sequence.get(0).getTimestamp(), jvFirst.getTimestamp());
377 // Unfortunately weights are double values, so must convert from long to double.
378 // TODO: need nano second precision? If so, use d.toNanos().
379 // TODO: risk of overflow when converting from long to double..?
380 graph.setEdgeWeight(edge, Long.valueOf(d.toMillis()).doubleValue());
382 // Alternative version if we cannot assume that sequences are ordered by timestamp:
383 // if (iv.sequence.stream().max(Comparator.comparing(PcapPacket::getTimestamp)).get()
384 // .getTimestamp().isBefore(jv.sequence.stream().min(
385 // Comparator.comparing(PcapPacket::getTimestamp)).get().getTimestamp())) {
392 // Graph construction complete, run shortest-path to find a (potential) signature match.
393 DijkstraShortestPath<Vertex, DefaultWeightedEdge> dijkstra = new DijkstraShortestPath<>(graph);
394 GraphPath<Vertex, DefaultWeightedEdge> shortestPath = dijkstra.getPath(source, sink);
395 if (shortestPath != null) {
396 // The total weight is the duration between the first packet of the first sequence and the last packet
397 // of the last sequence, so we simply have to compare the weight against the timeframe that we allow
398 // the signature to span. For now we just use the inclusion window we defined for training purposes.
399 // Note however, that we must convert back from double to long as the weight is stored as a double in
401 if (((long)shortestPath.getWeight()) < mInclusionTimeMillis) {
402 // There's a signature match!
403 // Extract the match from the vertices
404 List<List<PcapPacket>> signatureMatch = new ArrayList<>();
405 for(Vertex v : shortestPath.getVertexList()) {
406 if (v == source || v == sink) {
407 // Skip the dummy source and sink nodes.
410 signatureMatch.add(v.sequence);
411 // As there is a one-to-one correspondence between vertices[] and pendingMatches[], we know that
412 // the sequence we've "consumed" for index i of the matched signature is also at index i in
413 // pendingMatches. We must remove it from pendingMatches so that we don't use it to construct
414 // another signature match in a later call.
415 mPendingMatches[signatureMatch.size()-1].remove(v.sequence);
417 // Declare success: notify observers
418 mObservers.forEach(obs -> obs.onSignatureDetected(mSignature,
419 Collections.unmodifiableList(signatureMatch)));
426 * Encapsulates a {@code List<PcapPacket>} so as to allow the list to be used as a vertex in a graph while avoiding
427 * the expensive {@link AbstractList#equals(Object)} calls when adding vertices to the graph.
428 * Using this wrapper makes the incurred {@code equals(Object)} calls delegate to {@link Object#equals(Object)}
429 * instead of {@link AbstractList#equals(Object)}. The net effect is a faster implementation, but the graph will not
430 * recognize two lists that contain the same items--from a value and not reference point of view--as the same
431 * vertex. However, this is fine for our purposes -- in fact restricting it to reference equality seems more
434 private static class Vertex {
435 private final List<PcapPacket> sequence;
436 private Vertex(List<PcapPacket> wrappedSequence) {
437 sequence = wrappedSequence;