Changing the mechanism to count and correlate skipped packets.

[pingpong.git] / Code / Projects / PacketLevelSignatureExtractor / src / main / java / edu / uci / iotproject / detection / layer3 / Layer3ClusterMatcher.java

diff --git a/Code/Projects/PacketLevelSignatureExtractor/src/main/java/edu/uci/iotproject/detection/layer3/Layer3ClusterMatcher.java b/Code/Projects/PacketLevelSignatureExtractor/src/main/java/edu/uci/iotproject/detection/layer3/Layer3ClusterMatcher.java
index 53fab96201e8e71ae963f3510890794230c2213d..165cdb3e57f68de4319504a3fee4e15cd4efc34e 100644 (file)
--- a/Code/Projects/PacketLevelSignatureExtractor/src/main/java/edu/uci/iotproject/detection/layer3/Layer3ClusterMatcher.java
+++ b/Code/Projects/PacketLevelSignatureExtractor/src/main/java/edu/uci/iotproject/detection/layer3/Layer3ClusterMatcher.java
@@ -1,5 +1,6 @@
 package edu.uci.iotproject.detection.layer3;
 
+import edu.uci.iotproject.analysis.TriggerTrafficExtractor;
 import edu.uci.iotproject.detection.AbstractClusterMatcher;
 import edu.uci.iotproject.detection.ClusterMatcherObserver;
 import edu.uci.iotproject.trafficreassembly.layer3.Conversation;
@@ -44,19 +45,26 @@ public class Layer3ClusterMatcher extends AbstractClusterMatcher implements Pack
      */
     private final double mEps;
 
+    /**
+     * The packet inclusion time for signature.
+     */
+    private int mInclusionTimeMillis;
+
     /**
      * Create a {@link Layer3ClusterMatcher}.
      * @param cluster The cluster that traffic is matched against.
      * @param routerWanIp The router's WAN IP if examining traffic captured at the ISP's point of view (used for
      *                    determining the direction of packets).
-     * @param eps The epsilon value used in the DBSCAN algorithm.
+     * @param inclusionTimeMillis The packet inclusion time for signature.
      * @param isRangeBased The boolean that decides if it is range-based vs. strict matching.
+     * @param eps The epsilon value used in the DBSCAN algorithm.
      * @param detectionObservers Client code that wants to get notified whenever the {@link Layer3ClusterMatcher} detects that
      *                          (a subset of) the examined traffic is similar to the traffic that makes up
      *                          {@code cluster}, i.e., when the examined traffic is classified as pertaining to
      *                          {@code cluster}.
      */
-    public Layer3ClusterMatcher(List<List<PcapPacket>> cluster, String routerWanIp, boolean isRangeBased, double eps,
+    public Layer3ClusterMatcher(List<List<PcapPacket>> cluster, String routerWanIp, int inclusionTimeMillis,
+                                boolean isRangeBased, double eps,
                                 ClusterMatcherObserver... detectionObservers) {
         super(cluster, isRangeBased);
         Objects.requireNonNull(detectionObservers, "detectionObservers cannot be null");
@@ -83,6 +91,8 @@ public class Layer3ClusterMatcher extends AbstractClusterMatcher implements Pack
         }
         mEps = eps;
         mRouterWanIp = routerWanIp;
+        mInclusionTimeMillis =
+                inclusionTimeMillis == 0 ? TriggerTrafficExtractor.INCLUSION_WINDOW_MILLIS : inclusionTimeMillis;
     }
 
     @Override
@@ -122,6 +132,7 @@ public class Layer3ClusterMatcher extends AbstractClusterMatcher implements Pack
                     isPresent()) {
                 List<PcapPacket> matchSeq = match.get();
                 // Notify observers about the match.
+                // Max number of skipped packets in layer 3 is 0 (no skipped packets)
                 mObservers.forEach(o -> o.onMatch(Layer3ClusterMatcher.this, matchSeq));
                 /*
                  * Get the index in cPkts of the last packet in the sequence of packets that matches the searched
@@ -164,6 +175,7 @@ public class Layer3ClusterMatcher extends AbstractClusterMatcher implements Pack
                         isPresent()) {
                     List<PcapPacket> matchSeq = match.get();
                     // Notify observers about the match.
+                    // Max number of skipped packets in layer 3 is 0 (no skipped packets)
                     mObservers.forEach(o -> o.onMatch(Layer3ClusterMatcher.this, matchSeq));
                     /*
                      * Get the index in cPkts of the last packet in the sequence of packets that matches the searched
@@ -338,9 +350,16 @@ public class Layer3ClusterMatcher extends AbstractClusterMatcher implements Pack
             PcapPacket seqPkt = sequence.get(seqIdx);
             // We only have a match if packet lengths and directions match.
             // The packet lengths have to be in the range of [lowerBound - eps, upperBound+eps]
-            // TODO: Maybe we could do better here for the double to integer conversion?
-            int epsLowerBound = lowBndPkt.length() - (int) mEps;
-            int epsUpperBound = upBndPkt.length() + (int) mEps;
+            // We initialize the lower and upper bounds first
+            int epsLowerBound = lowBndPkt.length();
+            int epsUpperBound = upBndPkt.length();
+            // Do strict matching if the lower and upper bounds are the same length
+            // Do range matching with eps otherwise
+            if (epsLowerBound != epsUpperBound) {
+                // TODO: Maybe we could do better here for the double to integer conversion?
+                epsLowerBound = epsLowerBound - (int) mEps;
+                epsUpperBound = epsUpperBound + (int) mEps;
+            }
             if (epsLowerBound <= seqPkt.getOriginalLength() &&
                     seqPkt.getOriginalLength() <= epsUpperBound &&
                     subsequenceDirections[subseqIdx] == sequenceDirections[seqIdx]) {