1 package edu.uci.iotproject.util;
3 import edu.uci.iotproject.Conversation;
4 import edu.uci.iotproject.analysis.PcapPacketPair;
5 import edu.uci.iotproject.analysis.TcpConversationUtils;
6 import edu.uci.iotproject.analysis.TriggerTrafficExtractor;
7 import org.apache.commons.math3.stat.clustering.Cluster;
8 import org.pcap4j.core.PcapPacket;
9 import org.pcap4j.packet.EthernetPacket;
10 import org.pcap4j.packet.IpV4Packet;
11 import org.pcap4j.packet.TcpPacket;
12 import org.pcap4j.util.MacAddress;
17 * Utility methods for inspecting {@link PcapPacket} properties.
19 * @author Janus Varmarken {@literal <jvarmark@uci.edu>}
20 * @author Rahmadi Trimananda {@literal <rtrimana@uci.edu>}
22 public final class PcapPacketUtils {
25 * This is the threshold value for a signature's number of members
26 * If after a merging the number of members of a signature falls below this threshold, then we can boldly
27 * get rid of that signature.
29 private static final int SIGNATURE_MERGE_THRESHOLD = 5;
33 * Gets the source address of the Ethernet part of {@code packet}.
34 * @param packet The packet for which the Ethernet source address is to be extracted.
35 * @return The source address of the Ethernet part of {@code packet}.
37 public static MacAddress getEthSrcAddr(PcapPacket packet) {
38 return getEthernetPacketOrThrow(packet).getHeader().getSrcAddr();
42 * Gets the destination address of the Ethernet part of {@code packet}.
43 * @param packet The packet for which the Ethernet destination address is to be extracted.
44 * @return The destination address of the Ethernet part of {@code packet}.
46 public static MacAddress getEthDstAddr(PcapPacket packet) {
47 return getEthernetPacketOrThrow(packet).getHeader().getDstAddr();
51 * Determines if a given {@link PcapPacket} wraps a {@link TcpPacket}.
52 * @param packet The {@link PcapPacket} to inspect.
53 * @return {@code true} if {@code packet} wraps a {@link TcpPacket}, {@code false} otherwise.
55 public static boolean isTcp(PcapPacket packet) {
56 return packet.get(TcpPacket.class) != null;
60 * Gets the source IP (in decimal format) of an IPv4 packet.
61 * @param packet The packet for which the IPv4 source address is to be extracted.
62 * @return The decimal representation of the source IP of {@code packet} <em>iff</em> {@code packet} wraps an
64 * @throws NullPointerException if {@code packet} does not encapsulate an {@link IpV4Packet}.
66 public static String getSourceIp(PcapPacket packet) {
67 return getIpV4PacketOrThrow(packet).getHeader().getSrcAddr().getHostAddress();
71 * Gets the destination IP (in decimal format) of an IPv4 packet.
72 * @param packet The packet for which the IPv4 source address is to be extracted.
73 * @return The decimal representation of the destination IP of {@code packet} <em>iff</em> {@code packet} wraps an
75 * @throws NullPointerException if {@code packet} does not encapsulate an {@link IpV4Packet}.
77 public static String getDestinationIp(PcapPacket packet) {
78 return getIpV4PacketOrThrow(packet).getHeader().getDstAddr().getHostAddress();
82 * Gets the source port of a TCP packet.
83 * @param packet The packet for which the source port is to be extracted.
84 * @return The source port of the {@link TcpPacket} encapsulated by {@code packet}.
85 * @throws IllegalArgumentException if {@code packet} does not encapsulate a {@link TcpPacket}.
87 public static int getSourcePort(PcapPacket packet) {
88 TcpPacket tcpPacket = packet.get(TcpPacket.class);
89 if (tcpPacket == null) {
90 throw new IllegalArgumentException("not a TCP packet");
92 return tcpPacket.getHeader().getSrcPort().valueAsInt();
96 * Gets the destination port of a TCP packet.
97 * @param packet The packet for which the destination port is to be extracted.
98 * @return The destination port of the {@link TcpPacket} encapsulated by {@code packet}.
99 * @throws IllegalArgumentException if {@code packet} does not encapsulate a {@link TcpPacket}.
101 public static int getDestinationPort(PcapPacket packet) {
102 TcpPacket tcpPacket = packet.get(TcpPacket.class);
103 if (tcpPacket == null) {
104 throw new IllegalArgumentException("not a TCP packet");
106 return tcpPacket.getHeader().getDstPort().valueAsInt();
110 * Helper method to determine if the given combination of IP and port matches the source of the given packet.
111 * @param packet The packet to check.
112 * @param ip The IP to look for in the ip.src field of {@code packet}.
113 * @param port The port to look for in the tcp.port field of {@code packet}.
114 * @return {@code true} if the given ip+port match the corresponding fields in {@code packet}.
116 public static boolean isSource(PcapPacket packet, String ip, int port) {
117 IpV4Packet ipPacket = Objects.requireNonNull(packet.get(IpV4Packet.class));
118 // For now we only support TCP flows.
119 TcpPacket tcpPacket = Objects.requireNonNull(packet.get(TcpPacket.class));
120 String ipSrc = ipPacket.getHeader().getSrcAddr().getHostAddress();
121 int srcPort = tcpPacket.getHeader().getSrcPort().valueAsInt();
122 return ipSrc.equals(ip) && srcPort == port;
126 * Helper method to determine if the given combination of IP and port matches the destination of the given packet.
127 * @param packet The packet to check.
128 * @param ip The IP to look for in the ip.dst field of {@code packet}.
129 * @param port The port to look for in the tcp.dstport field of {@code packet}.
130 * @return {@code true} if the given ip+port match the corresponding fields in {@code packet}.
132 public static boolean isDestination(PcapPacket packet, String ip, int port) {
133 IpV4Packet ipPacket = Objects.requireNonNull(packet.get(IpV4Packet.class));
134 // For now we only support TCP flows.
135 TcpPacket tcpPacket = Objects.requireNonNull(packet.get(TcpPacket.class));
136 String ipDst = ipPacket.getHeader().getDstAddr().getHostAddress();
137 int dstPort = tcpPacket.getHeader().getDstPort().valueAsInt();
138 return ipDst.equals(ip) && dstPort == port;
142 * Checks if the source IP address of the {@link IpV4Packet} contained in {@code packet} is a local address, i.e.,
143 * if it pertains to subnet 10.0.0.0/8, 172.16.0.0/16, or 192.168.0.0/16.
144 * @param packet The packet for which the source IP address is to be examined.
145 * @return {@code true} if {@code packet} wraps a {@link IpV4Packet} for which the source IP address is a local IP
146 * address, {@code false} otherwise.
147 * @throws NullPointerException if {@code packet} does not encapsulate an {@link IpV4Packet}.
149 public static boolean isSrcIpLocal(PcapPacket packet) {
150 return getIpV4PacketOrThrow(packet).getHeader().getSrcAddr().isSiteLocalAddress();
154 * Checks if the destination IP address of the {@link IpV4Packet} contained in {@code packet} is a local address,
155 * i.e., if it pertains to subnet 10.0.0.0/8, 172.16.0.0/16, or 192.168.0.0/16.
156 * @param packet The packet for which the destination IP address is to be examined.
157 * @return {@code true} if {@code packet} wraps a {@link IpV4Packet} for which the destination IP address is a local
158 * IP address, {@code false} otherwise.
159 * @throws NullPointerException if {@code packet} does not encapsulate an {@link IpV4Packet}.
161 public static boolean isDstIpLocal(PcapPacket packet) {
162 return getIpV4PacketOrThrow(packet).getHeader().getDstAddr().isSiteLocalAddress();
166 * Checks if {@code packet} wraps a TCP packet that has the SYN flag set.
167 * @param packet A {@link PcapPacket} that is suspected to contain a {@link TcpPacket} for which the SYN flag is set.
168 * @return {@code true} <em>iff</em> {@code packet} contains a {@code TcpPacket} for which the SYN flag is set,
169 * {@code false} otherwise.
171 public static boolean isSyn(PcapPacket packet) {
172 TcpPacket tcp = packet.get(TcpPacket.class);
173 return tcp != null && tcp.getHeader().getSyn();
177 * Checks if {@code packet} wraps a TCP packet that has the ACK flag set.
178 * @param packet A {@link PcapPacket} that is suspected to contain a {@link TcpPacket} for which the ACK flag is set.
179 * @return {@code true} <em>iff</em> {@code packet} contains a {@code TcpPacket} for which the ACK flag is set,
180 * {@code false} otherwise.
182 public static boolean isAck(PcapPacket packet) {
183 TcpPacket tcp = packet.get(TcpPacket.class);
184 return tcp != null && tcp.getHeader().getAck();
188 * Transform a {@code Cluster} of {@code PcapPacketPair} objects into a {@code List} of {@code List} of
189 * {@code PcapPacket} objects.
190 * @param cluster A {@link Cluster} of {@link PcapPacketPair} objects that needs to be transformed.
191 * @return A {@link List} of {@link List} of {@link PcapPacket} objects as the result of the transformation.
193 public static List<List<PcapPacket>> clusterToListOfPcapPackets(Cluster<PcapPacketPair> cluster) {
194 List<List<PcapPacket>> ppListOfList = new ArrayList<>();
195 for (PcapPacketPair ppp: cluster.getPoints()) {
196 // Create a list of PcapPacket objects (list of two members).
197 List<PcapPacket> ppList = new ArrayList<>();
198 ppList.add(ppp.getFirst());
199 if(ppp.getSecond().isPresent())
200 ppList.add(ppp.getSecond().get());
203 // Create a list of list of PcapPacket objects.
204 ppListOfList.add(ppList);
206 // Sort the list of lists based on the first packet's timestamp!
207 Collections.sort(ppListOfList, (p1, p2) -> p1.get(0).getTimestamp().compareTo(p2.get(0).getTimestamp()));
212 * Merge signatures in {@code List} of {@code List} of {@code List} of {@code PcapPacket} objects.
213 * We cross-check these with {@code List} of {@code Conversation} objects to see
214 * if two {@code List} of {@code PcapPacket} objects actually belong to the same {@code Conversation}.
215 * @param signatures A {@link List} of {@link List} of {@link List} of
216 * {@link PcapPacket} objects that needs to be checked and merged.
217 * @param conversations A {@link List} of {@link Conversation} objects as reference for merging.
218 * @return A {@link List} of {@link List} of {@link List} of
219 * {@link PcapPacket} objects as the result of the merging.
221 public static List<List<List<PcapPacket>>>
222 mergeSignatures(List<List<List<PcapPacket>>> signatures, List<Conversation> conversations) {
224 // TODO: THIS IS NOT A DEEP COPY; IT BASICALLY CREATES A REFERENCE TO THE SAME LIST OBJECT
225 // List<List<List<PcapPacket>>> copySignatures = new ArrayList<>(signatures);
226 // Make a deep copy first.
227 List<List<List<PcapPacket>>> copySignatures = new ArrayList<>();
228 listDeepCopy(copySignatures, signatures);
229 // Traverse and look into the pairs of signatures.
230 for (int first = 0; first < signatures.size(); first++) {
231 List<List<PcapPacket>> firstList = signatures.get(first);
232 for (int second = first+1; second < signatures.size(); second++) {
233 int maxSignatureEl = 0; // Number of maximum signature elements.
234 List<List<PcapPacket>> secondList = signatures.get(second);
235 int initialSecondListMembers = secondList.size();
236 // Iterate over the signatures in the first list.
237 for (List<PcapPacket> signature : firstList) {
238 signature.removeIf(el -> el == null); // Clean up null elements.
239 // Return the Conversation that the signature is part of.
240 Conversation conv = TcpConversationUtils.returnConversation(signature, conversations);
241 // Find the element of the second list that is a match for that Conversation.
242 for (List<PcapPacket> ppList : secondList) {
243 ppList.removeIf(el -> el == null); // Clean up null elements.
244 // Check if they are part of a Conversation and are adjacent to the first signature.
245 // If yes then merge into the first list.
246 TcpConversationUtils.SignaturePosition position =
247 TcpConversationUtils.isPartOfConversationAndAdjacent(signature, ppList, conv);
248 if (position == TcpConversationUtils.SignaturePosition.LEFT_ADJACENT) {
249 // Merge to the left side of the first signature.
250 ppList.addAll(signature);
252 maxSignatureEl = signature.size() > maxSignatureEl ? signature.size() : maxSignatureEl;
253 secondList.remove(ppList); // Remove as we merge.
255 } else if (position == TcpConversationUtils.SignaturePosition.RIGHT_ADJACENT) {
256 // Merge to the right side of the first signature.
257 signature.addAll(ppList);
258 maxSignatureEl = signature.size() > maxSignatureEl ? signature.size() : maxSignatureEl;
259 secondList.remove(ppList); // Remove as we merge.
261 } // TcpConversationUtils.SignaturePosition.NOT_ADJACENT.
264 // Call it a successful merging if there are only less than 5 elements from the second list that
266 if (secondList.size() < SIGNATURE_MERGE_THRESHOLD) {
267 // Prune the unsuccessfully merged signatures (i.e., these will have size() < maxSignatureEl).
268 final int maxNumOfEl = maxSignatureEl;
269 // TODO: DOUBLE CHECK IF WE REALLY NEED TO PRUNE FAILED BINDINGS
270 // TODO: SOMETIMES THE SEQUENCES ARE JUST INCOMPLETE
271 // TODO: AND BOTH THE COMPLETE AND INCOMPLETE SEQUENCES ARE VALID SIGNATURES!
272 firstList.removeIf(el -> el.size() < maxNumOfEl);
273 // Remove the merged set of signatures when successful.
274 signatures.remove(secondList);
275 } else if (secondList.size() < initialSecondListMembers) {
276 // If only some of the signatures from the second list are merged, this means UNSUCCESSFUL merging.
277 // Return the original copy of the signatures object.
278 return copySignatures;
286 * Deep copy to create an entirely new {@link List} of {@link List} of {@link List} of {@link PcapPacket} objects.
287 * @param destList A {@link List} of {@link List} of {@link List} of
288 * {@link PcapPacket} objects that will be the final container of the deep copy
289 * @param sourceList A {@link List} of {@link List} of {@link List} of
290 * {@link PcapPacket} objects that will be the source of the deep copy.
292 private static void listDeepCopy(List<List<List<PcapPacket>>> destList, List<List<List<PcapPacket>>> sourceList) {
294 for(List<List<PcapPacket>> llPcapPacket : sourceList) {
295 List<List<PcapPacket>> tmpListOfList = new ArrayList<>();
296 for(List<PcapPacket> lPcapPacket : llPcapPacket) {
297 List<PcapPacket> tmpList = new ArrayList<>();
298 for(PcapPacket pcapPacket : lPcapPacket) {
299 tmpList.add(pcapPacket);
301 tmpListOfList.add(tmpList);
303 destList.add(tmpListOfList);
308 * Sort the signatures in the {@code List} of {@code List} of {@code List} of {@code PcapPacket} objects.
309 * The purpose of this is to sort the order of signatures in the signature list. For detection purposes, we need
310 * to know if one signature occurs earlier/later in time with respect to the other signatures for more confidence
311 * in detecting the occurrence of an event.
312 * @param signatures A {@code List} of {@code List} of {@code List} of {@code PcapPacket} objects that needs sorting.
313 * We assume that innermost {@code List} of {@code PcapPacket} objects have been sorted ascending
314 * by timestamps. By the time we use this method, we should have sorted it when calling the
315 * {@code clusterToListOfPcapPackets} method.
316 * @return A sorted {@code List} of {@code List} of {@code List} of {@code PcapPacket} objects.
318 public static List<List<List<PcapPacket>>> sortSignatures(List<List<List<PcapPacket>>> signatures) {
319 // TODO: This is the simplest solution!!! Might not cover all corner cases.
320 // TODO: Sort the list of lists based on the first packet's timestamps!
321 //Collections.sort(signatures, (p1, p2) -> {
322 // return p1.get(0).get(0).getTimestamp().compareTo(p2.get(0).get(0).getTimestamp());
324 // TODO: The following is a more complete solution that covers corner cases.
325 // Sort the list of lists based on one-to-one comparison between timestamps of signatures on both lists.
326 // This also takes into account the fact that the number of signatures in the two lists could be different.
327 // Additionally, this code forces the comparison between two signatures only if they occur in the
328 // INCLUSION_WINDOW_MILLIS window; otherwise, it tries to find the right pair of signatures in the time window.
329 Collections.sort(signatures, (p1, p2) -> {
334 // Need to make sure that both are not out of bound!
335 while (count1 + 1 < p1.size() && count2 + 1 < p2.size()) {
336 long timestamp1 = p1.get(count1).get(0).getTimestamp().toEpochMilli();
337 long timestamp2 = p2.get(count2).get(0).getTimestamp().toEpochMilli();
338 // The two timestamps have to be within a 15-second window!
339 if (Math.abs(timestamp1 - timestamp2) < TriggerTrafficExtractor.INCLUSION_WINDOW_MILLIS) {
340 // If these two are within INCLUSION_WINDOW_MILLIS window then compare!
341 compare = p1.get(count1).get(0).getTimestamp().compareTo(p2.get(count2).get(0).getTimestamp());
342 if (comparePrev != 0) { // First time since it is 0
343 if (Integer.signum(compare) != Integer.signum(comparePrev)) {
344 // Throw an exception if the order of the two signatures is not consistent,
345 // E.g., 111, 222, 333 in one occassion and 222, 333, 111 in the other.
346 // throw new Error("For some reason, the order of signatures are not always consistent!" +
347 // "Returning the original data structure of signatures...");
350 comparePrev = compare;
354 // If not within INCLUSION_WINDOW_MILLIS window then find the correct pair
355 // by incrementing one of them.
356 if (timestamp1 < timestamp2)
368 * Gets the {@link IpV4Packet} contained in {@code packet}, or throws a {@link NullPointerException} if
369 * {@code packet} does not contain an {@link IpV4Packet}.
370 * @param packet A {@link PcapPacket} that is expected to contain an {@link IpV4Packet}.
371 * @return The {@link IpV4Packet} contained in {@code packet}.
372 * @throws NullPointerException if {@code packet} does not encapsulate an {@link IpV4Packet}.
374 private static IpV4Packet getIpV4PacketOrThrow(PcapPacket packet) {
375 return Objects.requireNonNull(packet.get(IpV4Packet.class), "not an IPv4 packet");
379 * Gets the {@link EthernetPacket} contained in {@code packet}, or throws a {@link NullPointerException} if
380 * {@code packet} does not contain an {@link EthernetPacket}.
381 * @param packet A {@link PcapPacket} that is expected to contain an {@link EthernetPacket}.
382 * @return The {@link EthernetPacket} contained in {@code packet}.
383 * @throws NullPointerException if {@code packet} does not encapsulate an {@link EthernetPacket}.
385 private static final EthernetPacket getEthernetPacketOrThrow(PcapPacket packet) {
386 return Objects.requireNonNull(packet.get(EthernetPacket.class), "not an Ethernet packet");
390 * Print signatures in {@code List} of {@code List} of {@code List} of {@code PcapPacket} objects.
392 * @param signatures A {@link List} of {@link List} of {@link List} of
393 * {@link PcapPacket} objects that needs to be printed.
395 public static void printSignatures(List<List<List<PcapPacket>>> signatures) {
397 // Iterate over the list of all clusters/sequences
398 int sequenceCounter = 0;
399 for(List<List<PcapPacket>> listListPcapPacket : signatures) {
400 // Iterate over every member of a cluster/sequence
401 System.out.print("====== SEQUENCE " + sequenceCounter++);
402 System.out.println(" - " + listListPcapPacket.size() + " MEMBERS ======");
403 for(List<PcapPacket> listPcapPacket : listListPcapPacket) {
404 // Print out packet lengths in a sequence
405 int packetCounter = 0;
406 for(PcapPacket pcapPacket : listPcapPacket) {
407 if(pcapPacket != null) {
408 System.out.print(pcapPacket.length());
410 if(packetCounter < listPcapPacket.size() - 1) {
411 System.out.print(" "); // Provide space if not last packet
413 System.out.println(); // Newline if last packet
422 * Remove a sequence in a signature object.
424 * @param signatures A {@link List} of {@link List} of {@link List} of
425 * {@link PcapPacket} objects.
426 * @param sequenceIndex An index for a sequence that consists of {{@link List} of {@link List} of
427 * {@link PcapPacket} objects.
429 public static void removeSequenceFromSignature(List<List<List<PcapPacket>>> signatures, int sequenceIndex) {
431 // Sequence index starts from 0
432 signatures.remove(sequenceIndex);