// TODO: what if there is long time between response and reply packet? Should we add a threshold and exclude those cases?
}
-
/**
- * Given a list of TCP conversations and associated DNS mappings, groups the conversations by hostname.
- * @param tcpConversations The list of TCP conversations.
+ * Given a collection of TCP conversations and associated DNS mappings, groups the conversations by hostname.
+ * @param tcpConversations The collection of TCP conversations.
* @param ipHostnameMappings The associated DNS mappings.
* @return A map where each key is a hostname and its associated value is a list of conversations where one of the
* two communicating hosts is that hostname (i.e. its IP maps to the hostname).
*/
- public static Map<String, List<Conversation>> groupConversationsByHostname(List<Conversation> tcpConversations, DnsMap ipHostnameMappings) {
+ public static Map<String, List<Conversation>> groupConversationsByHostname(Collection<Conversation> tcpConversations, DnsMap ipHostnameMappings) {
HashMap<String, List<Conversation>> result = new HashMap<>();
for (Conversation c : tcpConversations) {
if (c.getPackets().size() == 0) {
return result;
}
+ public static Map<String, Integer> countPacketSequenceFrequencies(Collection<Conversation> conversations) {
+ Map<String, Integer> result = new HashMap<>();
+ for (Conversation conv : conversations) {
+ if (conv.getPackets().size() == 0) {
+ // Skip conversations with no payload packets.
+ continue;
+ }
+ StringBuilder sb = new StringBuilder();
+ for (PcapPacket pp : conv.getPackets()) {
+ sb.append(pp.length() + " ");
+ }
+ result.merge(sb.toString(), 1, (i1, i2) -> i1+i2);
+ }
+ return result;
+ }
+
+ /**
+ * Given a {@link Conversation}, counts the frequencies of each unique packet length seen as part of the
+ * {@code Conversation}.
+ * @param c The {@code Conversation} for which unique packet length frequencies are to be determined.
+ * @return A mapping from packet length to its frequency.
+ */
+ public static Map<Integer, Integer> countPacketLengthFrequencies(Conversation c) {
+ Map<Integer, Integer> result = new HashMap<>();
+ for (PcapPacket packet : c.getPackets()) {
+ result.merge(packet.length(), 1, (i1, i2) -> i1 + i2);
+ }
+ return result;
+ }
+
+ /**
+ * Like {@link #countPacketLengthFrequencies(Conversation)}, but counts packet length frequencies for a collection
+ * of {@code Conversation}s, i.e., the frequency of a packet length becomes the total number of packets with that
+ * length across <em>all</em> {@code Conversation}s in {@code conversations}.
+ * @param conversations The collection of {@code Conversation}s for which packet length frequencies are to be
+ * counted.
+ * @return A mapping from packet length to its frequency.
+ */
+ public static Map<Integer, Integer> countPacketLengthFrequencies(Collection<Conversation> conversations) {
+ Map<Integer, Integer> result = new HashMap<>();
+ for (Conversation c : conversations) {
+ Map<Integer, Integer> intermediateResult = countPacketLengthFrequencies(c);
+ for (Map.Entry<Integer, Integer> entry : intermediateResult.entrySet()) {
+ result.merge(entry.getKey(), entry.getValue(), (i1, i2) -> i1 + i2);
+ }
+ }
+ return result;
+ }
+
+ public static Map<String, Integer> countPacketPairFrequencies(Collection<PcapPacketPair> pairs) {
+ Map<String, Integer> result = new HashMap<>();
+ for (PcapPacketPair ppp : pairs) {
+ result.merge(ppp.toString(), 1, (i1, i2) -> i1 + i2);
+ }
+ return result;
+ }
}