+++ /dev/null
-package edu.uci.iotproject.detection.layer3;
-
-import edu.uci.iotproject.detection.AbstractClusterMatcher;
-import edu.uci.iotproject.detection.ClusterMatcherObserver;
-import edu.uci.iotproject.trafficreassembly.layer3.Conversation;
-import edu.uci.iotproject.trafficreassembly.layer3.TcpReassembler;
-import edu.uci.iotproject.analysis.TcpConversationUtils;
-import edu.uci.iotproject.io.PcapHandleReader;
-import edu.uci.iotproject.util.PrintUtils;
-import org.pcap4j.core.*;
-
-import java.time.ZoneId;
-import java.util.*;
-import java.util.stream.Collectors;
-
-import static edu.uci.iotproject.util.PcapPacketUtils.*;
-
-/**
- * Searches a traffic trace for sequences of packets "belong to" a given cluster (in other words, attempts to classify
- * traffic as pertaining to a given cluster).
- *
- * @author Janus Varmarken {@literal <jvarmark@uci.edu>}
- * @author Rahmadi Trimananda {@literal <rtrimana@uci.edu>}
- */
-public class Layer3ClusterMatcher extends AbstractClusterMatcher implements PacketListener {
-
- // Test client
- public static void main(String[] args) throws PcapNativeException, NotOpenException {
-
-// String path = "/scratch/July-2018"; // Rahmadi
- String path = "/Users/varmarken/temp/UCI IoT Project/experiments"; // Janus
- final String inputPcapFile = path + "/2018-07/dlink/dlink.wlan1.local.pcap";
- final String signatureFile = path + "/2018-07/dlink/offSignature1.sig";
-
- List<List<PcapPacket>> signature = PrintUtils.deserializeClustersFromFile(signatureFile);
- Layer3ClusterMatcher clusterMatcher = new Layer3ClusterMatcher(signature, null,
- (sig, match) -> System.out.println(
- String.format("[ !!! SIGNATURE DETECTED AT %s !!! ]",
- match.get(0).getTimestamp().atZone(ZoneId.of("America/Los_Angeles")))
- )
- );
-
- PcapHandle handle;
- try {
- handle = Pcaps.openOffline(inputPcapFile, PcapHandle.TimestampPrecision.NANO);
- } catch (PcapNativeException pne) {
- handle = Pcaps.openOffline(inputPcapFile);
- }
- PcapHandleReader reader = new PcapHandleReader(handle, p -> true, clusterMatcher);
- reader.readFromHandle();
- clusterMatcher.performDetection();
- }
-
- /**
- * The ordered directions of packets in the sequences that make up {@link #mCluster}.
- */
- private final Conversation.Direction[] mClusterMemberDirections;
-
- /**
- * For reassembling the observed traffic into TCP connections.
- */
- private final TcpReassembler mTcpReassembler = new TcpReassembler();
-
- /**
- * IP of the router's WAN port (if analyzed traffic is captured at the ISP's point of view).
- */
- private final String mRouterWanIp;
-
- /**
- * 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 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,
- ClusterMatcherObserver... detectionObservers) {
- super(cluster);
- Objects.requireNonNull(detectionObservers, "detectionObservers cannot be null");
- for (ClusterMatcherObserver obs : detectionObservers) {
- addObserver(obs);
- }
- // Build the cluster members' direction sequence.
- // Note: assumes that the provided cluster was captured within the local network (routerWanIp is set to null).
- mClusterMemberDirections = getPacketDirections(cluster.get(0), null);
- /*
- * Enforce restriction on cluster members: all representatives must exhibit the same direction pattern and
- * contain the same number of packets. Note that this is a somewhat heavy operation, so it may be disabled later
- * on in favor of performance. However, it is only run once (at instantiation), so the overhead may be warranted
- * in order to ensure correctness, especially during the development/debugging phase.
- */
- if (mCluster.stream().
- anyMatch(inner -> !Arrays.equals(mClusterMemberDirections, getPacketDirections(inner, null)))) {
- throw new IllegalArgumentException(
- "cluster members must contain the same number of packets and exhibit the same packet direction " +
- "pattern"
- );
- }
- mRouterWanIp = routerWanIp;
- }
-
- @Override
- public void gotPacket(PcapPacket packet) {
- // Present packet to TCP reassembler so that it can be mapped to a connection (if it is a TCP packet).
- mTcpReassembler.gotPacket(packet);
- }
-
- /**
- * Get the cluster that describes the packet sequence that this {@link Layer3ClusterMatcher} is searching for.
- * @return the cluster that describes the packet sequence that this {@link Layer3ClusterMatcher} is searching for.
- */
- public List<List<PcapPacket>> getCluster() {
- return mCluster;
- }
-
- public void performDetection() {
- /*
- * Let's start out simple by building a version that only works for signatures that do not span across multiple
- * TCP conversations...
- */
- for (Conversation c : mTcpReassembler.getTcpConversations()) {
- if (c.isTls() && c.getTlsApplicationDataPackets().isEmpty() || !c.isTls() && c.getPackets().isEmpty()) {
- // Skip empty conversations.
- continue;
- }
- for (List<PcapPacket> signatureSequence : mCluster) {
- if (isTlsSequence(signatureSequence) != c.isTls()) {
- // We consider it a mismatch if one is a TLS application data sequence and the other is not.
- continue;
- }
- // Fetch set of packets to examine based on TLS or not.
- List<PcapPacket> cPkts = c.isTls() ? c.getTlsApplicationDataPackets() : c.getPackets();
- /*
- * Note: we embed the attempt to detect the signature sequence in a loop in order to capture those cases
- * where the same signature sequence appears multiple times in one Conversation.
- *
- * Note: since we expect all sequences that together make up the signature to exhibit the same direction
- * pattern, we can simply pass the precomputed direction array for the signature sequence so that it
- * won't have to be recomputed internally in each call to findSubsequenceInSequence().
- */
- Optional<List<PcapPacket>> match;
- while ((match = findSubsequenceInSequence(signatureSequence, cPkts, mClusterMemberDirections, null)).
- isPresent()) {
- List<PcapPacket> matchSeq = match.get();
- // Notify observers about the match.
- 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
- * signature sequence.
- */
- int matchSeqEndIdx = cPkts.indexOf(matchSeq.get(matchSeq.size()-1));
- // We restart the search for the signature sequence immediately after that index, so truncate cPkts.
- cPkts = cPkts.stream().skip(matchSeqEndIdx + 1).collect(Collectors.toList());
- }
- }
- /*
- * TODO:
- * if no item in cluster matches, also perform a distance-based matching to cover those cases where we did
- * not manage to capture every single mutation of the sequence during training.
- *
- * Need to compute average/centroid of cluster to do so...? Compute within-cluster variance, then check if
- * distance between input conversation and cluster average/centroid is smaller than or equal to the computed
- * variance?
- */
- }
- }
-
- /**
- * Checks if {@code sequence} is a sequence of TLS packets. Note: the current implementation relies on inspection
- * of the port numbers when deciding between TLS vs. non-TLS. Therefore, only the first packet of {@code sequence}
- * is examined as it is assumed that all packets in {@code sequence} pertain to the same {@link Conversation} and
- * hence share the same set of two src/dst port numbers (albeit possibly alternating between which one is the src
- * and which one is the dst, as packets in {@code sequence} may be in alternating directions).
- * @param sequence The sequence of packets for which it is to be determined if it is a sequence of TLS packets or
- * non-TLS packets.
- * @return {@code true} if {@code sequence} is a sequence of TLS packets, {@code false} otherwise.
- */
- private boolean isTlsSequence(List<PcapPacket> sequence) {
- // NOTE: Assumes ALL packets in sequence pertain to the same TCP connection!
- PcapPacket firstPkt = sequence.get(0);
- int srcPort = getSourcePort(firstPkt);
- int dstPort = getDestinationPort(firstPkt);
- return TcpConversationUtils.isTlsPort(srcPort) || TcpConversationUtils.isTlsPort(dstPort);
- }
-
- /**
- * Examine if a given sequence of packets ({@code sequence}) contains a given shorter sequence of packets
- * ({@code subsequence}). Note: the current implementation actually searches for a substring as it does not allow
- * for interleaving packets in {@code sequence} that are not in {@code subsequence}; for example, if
- * {@code subsequence} consists of packet lengths [2, 3, 5] and {@code sequence} consists of packet lengths
- * [2, 3, 4, 5], the result will be that there is no match (because of the interleaving 4). If we are to allow
- * interleaving packets, we need a modified version of
- * <a href="https://stackoverflow.com/a/20545604/1214974">this</a>.
- *
- * @param subsequence The sequence to search for.
- * @param sequence The sequence to search.
- * @param subsequenceDirections The directions of packets in {@code subsequence} such that for all {@code i},
- * {@code subsequenceDirections[i]} is the direction of the packet returned by
- * {@code subsequence.get(i)}. May be set to {@code null}, in which this call will
- * internally compute the packet directions.
- * @param sequenceDirections The directions of packets in {@code sequence} such that for all {@code i},
- * {@code sequenceDirections[i]} is the direction of the packet returned by
- * {@code sequence.get(i)}. May be set to {@code null}, in which this call will internally
- * compute the packet directions.
- *
- * @return An {@link Optional} containing the part of {@code sequence} that matches {@code subsequence}, or an empty
- * {@link Optional} if no part of {@code sequence} matches {@code subsequence}.
- */
- private Optional<List<PcapPacket>> findSubsequenceInSequence(List<PcapPacket> subsequence,
- List<PcapPacket> sequence,
- Conversation.Direction[] subsequenceDirections,
- Conversation.Direction[] sequenceDirections) {
- if (sequence.size() < subsequence.size()) {
- // If subsequence is longer, it cannot be contained in sequence.
- return Optional.empty();
- }
- if (isTlsSequence(subsequence) != isTlsSequence(sequence)) {
- // We consider it a mismatch if one is a TLS application data sequence and the other is not.
- return Optional.empty();
- }
- // If packet directions have not been precomputed by calling code, we need to construct them.
- if (subsequenceDirections == null) {
- subsequenceDirections = getPacketDirections(subsequence, mRouterWanIp);
- }
- if (sequenceDirections == null) {
- sequenceDirections = getPacketDirections(sequence, mRouterWanIp);
- }
- int subseqIdx = 0;
- int seqIdx = 0;
- while (seqIdx < sequence.size()) {
- PcapPacket subseqPkt = subsequence.get(subseqIdx);
- PcapPacket seqPkt = sequence.get(seqIdx);
- // We only have a match if packet lengths and directions match.
- if (subseqPkt.getOriginalLength() == seqPkt.getOriginalLength() &&
- subsequenceDirections[subseqIdx] == sequenceDirections[seqIdx]) {
- // A match; advance both indices to consider next packet in subsequence vs. next packet in sequence.
- subseqIdx++;
- seqIdx++;
- if (subseqIdx == subsequence.size()) {
- // We managed to match the entire subsequence in sequence.
- // Return the sublist of sequence that matches subsequence.
- /*
- * TODO:
- * ASSUMES THE BACKING LIST (i.e., 'sequence') IS _NOT_ STRUCTURALLY MODIFIED, hence may not work
- * for live traces!
- */
- return Optional.of(sequence.subList(seqIdx - subsequence.size(), seqIdx));
- }
- } else {
- // Mismatch.
- if (subseqIdx > 0) {
- /*
- * If we managed to match parts of subsequence, we restart the search for subsequence in sequence at
- * the index of sequence where the current mismatch occurred. I.e., we must reset subseqIdx, but
- * leave seqIdx untouched.
- */
- subseqIdx = 0;
- } else {
- /*
- * First packet of subsequence didn't match packet at seqIdx of sequence, so we move forward in
- * sequence, i.e., we continue the search for subsequence in sequence starting at index seqIdx+1 of
- * sequence.
- */
- seqIdx++;
- }
- }
- }
- return Optional.empty();
- }
-
- /**
- * Given a cluster, produces a pruned version of that cluster. In the pruned version, there are no duplicate cluster
- * members. Two cluster members are considered identical if their packets lengths and packet directions are
- * identical. The resulting pruned cluster is unmodifiable (this applies to both the outermost list as well as the
- * nested lists) in order to preserve its integrity when exposed to external code (e.g., through
- * {@link #getCluster()}).
- *
- * @param cluster A cluster to prune.
- * @return The resulting pruned cluster.
- */
- @Override
- protected List<List<PcapPacket>> pruneCluster(List<List<PcapPacket>> cluster) {
- List<List<PcapPacket>> prunedCluster = new ArrayList<>();
- for (List<PcapPacket> originalClusterSeq : cluster) {
- boolean alreadyPresent = false;
- for (List<PcapPacket> prunedClusterSeq : prunedCluster) {
- Optional<List<PcapPacket>> duplicate = findSubsequenceInSequence(originalClusterSeq, prunedClusterSeq,
- mClusterMemberDirections, mClusterMemberDirections);
- if (duplicate.isPresent()) {
- alreadyPresent = true;
- break;
- }
- }
- if (!alreadyPresent) {
- prunedCluster.add(Collections.unmodifiableList(originalClusterSeq));
- }
- }
- return Collections.unmodifiableList(prunedCluster);
- }
-
- /**
- * Given a {@code List<PcapPacket>}, generate a {@code Conversation.Direction[]} such that each entry in the
- * resulting {@code Conversation.Direction[]} specifies the direction of the {@link PcapPacket} at the corresponding
- * index in the input list.
- * @param packets The list of packets for which to construct a corresponding array of packet directions.
- * @param routerWanIp The IP of the router's WAN port. This is used for determining the direction of packets when
- * the traffic is captured just outside the local network (at the ISP side of the router). Set to
- * {@code null} if {@code packets} stem from traffic captured within the local network.
- * @return A {@code Conversation.Direction[]} specifying the direction of the {@link PcapPacket} at the
- * corresponding index in {@code packets}.
- */
- private static Conversation.Direction[] getPacketDirections(List<PcapPacket> packets, String routerWanIp) {
- Conversation.Direction[] directions = new Conversation.Direction[packets.size()];
- for (int i = 0; i < packets.size(); i++) {
- PcapPacket pkt = packets.get(i);
- if (getSourceIp(pkt).equals(getDestinationIp(pkt))) {
- // Sanity check: we shouldn't be processing loopback traffic
- throw new AssertionError("loopback traffic detected");
- }
- if (isSrcIpLocal(pkt) || getSourceIp(pkt).equals(routerWanIp)) {
- directions[i] = Conversation.Direction.CLIENT_TO_SERVER;
- } else if (isDstIpLocal(pkt) || getDestinationIp(pkt).equals(routerWanIp)) {
- directions[i] = Conversation.Direction.SERVER_TO_CLIENT;
- } else {
- //throw new IllegalArgumentException("no local IP or router WAN port IP found, can't detect direction");
- }
- }
- return directions;
- }
-
-}
projects / pingpong.git / blobdiff