Refactoring and restructuring - Adding DnsMap class
authorrtrimana <rtrimana@uci.edu>
Tue, 1 May 2018 23:53:21 +0000 (16:53 -0700)
committerrtrimana <rtrimana@uci.edu>
Tue, 1 May 2018 23:53:21 +0000 (16:53 -0700)
Code/Projects/SmartPlugDetector/src/main/java/edu/uci/iotproject/DnsMap.java [new file with mode: 0644]
Code/Projects/SmartPlugDetector/src/main/java/edu/uci/iotproject/FlowPatternFinder.java
Code/Projects/SmartPlugDetector/src/main/java/edu/uci/iotproject/Main.java

diff --git a/Code/Projects/SmartPlugDetector/src/main/java/edu/uci/iotproject/DnsMap.java b/Code/Projects/SmartPlugDetector/src/main/java/edu/uci/iotproject/DnsMap.java
new file mode 100644 (file)
index 0000000..d2f91f3
--- /dev/null
@@ -0,0 +1,104 @@
+package edu.uci.iotproject;
+
+import org.pcap4j.packet.Packet;
+import org.pcap4j.packet.DnsPacket;
+import org.pcap4j.packet.DnsResourceRecord;
+import org.pcap4j.packet.namednumber.DnsResourceRecordType;
+
+import java.io.EOFException;
+import java.net.Inet4Address;
+import java.net.UnknownHostException;
+import java.time.Instant;
+import java.util.*;
+import java.util.concurrent.TimeoutException;
+
+/**
+ * This is a class that does DNS mapping.
+ * Basically an IP address is mapped to its
+ * respective DNS hostnames.
+ *
+ * @author Rahmadi Trimananda (rtrimana@uci.edu)
+ * @version 0.1
+ */
+public class DnsMap {
+
+    /* Class properties */
+    private Map<String, Set<String>> ipToHostnameMap;
+
+    /* Class constants */
+    private static final Set<String> EMPTY_SET = Collections.unmodifiableSet(new HashSet<>());
+
+    
+    /* Constructor */
+    public DnsMap() {
+
+        ipToHostnameMap = new HashMap<String, Set<String>>();
+    }
+
+    
+    /**
+     * Gets a packet and determine if this is a DNS packet
+     *
+     * @param   packet  Packet object
+     * @return          DnsPacket object or null
+     */
+    private DnsPacket getDnsPacket(Packet packet) {
+
+        DnsPacket dnsPacket = packet.get(DnsPacket.class);
+        return dnsPacket;
+    }
+
+
+    /**
+     * Checks DNS packet and build the map data structure that
+     * maps IP addresses to DNS hostnames
+     *
+     * @param   packet  Packet object
+     */
+    public void validateAndAddNewEntry(Packet packet) throws UnknownHostException {
+
+        // Make sure that this is a DNS packet
+        DnsPacket dnsPacket = getDnsPacket(packet);
+        if (dnsPacket != null) {
+
+            // We only care about DNS answers
+            if (dnsPacket.getHeader().getAnswers().size() != 0) {
+
+                String hostname = dnsPacket.getHeader().getQuestions().get(0).getQName().getName();
+                for(DnsResourceRecord answer : dnsPacket.getHeader().getAnswers()) {
+                    // We only care about type A records
+                    if (!answer.getDataType().equals(DnsResourceRecordType.A))
+                        continue;
+                    // Sanity check. For some reason the hostname appears to be the empty string in the answer .
+                    // We hence have to assume that all answers correspond to a single question that holds the hostname as part of its object tree.
+                    // Therefore, if there are more questions in one query-reply exchange, we are in trouble.
+                    if (!answer.getName().getName().equals("") && !answer.getName().getName().equals(hostname))
+                        throw new RuntimeException("[DNS parser] mismatch between hostname in question and hostname in answer");
+                    // The IP in byte representation.
+                    byte[] ipBytes = answer.getRData().getRawData();
+                    // Convert to string representation.
+                    String ip = Inet4Address.getByAddress(ipBytes).getHostAddress();
+                    Set<String> hostnameSet = new HashSet<String>();
+                    hostnameSet.add(hostname);
+                    // Update or insert depending on presence of key:
+                    // Concat the existing set and the new set if ip already present as key,
+                    // otherwise add an entry for ip pointing to new set.
+                    ipToHostnameMap.merge(ip, hostnameSet, (v1, v2) -> { v1.addAll(v2); return v1; });
+                }
+            }
+        }
+    }
+    
+    
+    /**
+     * Checks DNS packet and build the map data structure that
+     * maps IP addresses to DNS hostnames
+     *
+     * @param   address     Address to check
+     * @param   hostname    Hostname to check
+     */
+    public boolean isRelatedToCloudServer(String address, String hostname) {
+        
+        return ipToHostnameMap.getOrDefault(address, EMPTY_SET).contains(hostname);
+    }
+}
index 8c7d41e..86b1a57 100644 (file)
@@ -7,8 +7,10 @@ import org.pcap4j.core.PcapPacket;
 import org.pcap4j.packet.IpV4Packet;
 import org.pcap4j.packet.Packet;
 import org.pcap4j.packet.TcpPacket;
+import org.pcap4j.packet.DnsPacket;
 
 import java.io.EOFException;
+import java.net.UnknownHostException;
 import java.time.Instant;
 import java.util.*;
 import java.util.concurrent.TimeoutException;
@@ -20,23 +22,25 @@ import java.util.concurrent.TimeoutException;
  */
 public class FlowPatternFinder {
 
-    private final Map<String, Set<String>> dnsMap;
+    /* Class properties */
     private final Map<Conversation, List<PcapPacket>> connections = new HashMap<>();
-
-    public FlowPatternFinder(Map<String, Set<String>> dnsMap) {
-        this.dnsMap = Objects.requireNonNull(dnsMap);
+    
+    private DnsMap dnsMap;
+    
+    public FlowPatternFinder() {
+        this.dnsMap = new DnsMap();
     }
 
-    private static final Set<String> EMPTY_SET = Collections.unmodifiableSet(new HashSet<>());
-
     // TODO clean up exceptions etc.
     public void findFlowPattern(PcapHandle pcap, FlowPattern pattern)
             throws PcapNativeException, NotOpenException, TimeoutException {
+        int counter = 0;
         try {
             PcapPacket packet;
-
             while ((packet = pcap.getNextPacketEx()) != null) {
 
+                // Check if this is a valid DNS packet
+                dnsMap.validateAndAddNewEntry(packet);
                 // For now, we only work support pattern search in TCP over IPv4.
                 IpV4Packet ipPacket = packet.get(IpV4Packet.class);
                 TcpPacket tcpPacket = packet.get(TcpPacket.class);
@@ -48,9 +52,9 @@ public class FlowPatternFinder {
                 int srcPort = tcpPacket.getHeader().getSrcPort().valueAsInt();
                 int dstPort = tcpPacket.getHeader().getDstPort().valueAsInt();
                 // Is this packet related to the pattern and coming from the cloud server?
-                boolean fromServer = dnsMap.getOrDefault(srcAddress, EMPTY_SET).contains(pattern.getHostname());
+                boolean fromServer = dnsMap.isRelatedToCloudServer(srcAddress, pattern.getHostname());
                 // Is this packet related to the pattern and going to the cloud server?
-                boolean fromClient = dnsMap.getOrDefault(dstAddress, EMPTY_SET).contains(pattern.getHostname());
+                boolean fromClient = dnsMap.isRelatedToCloudServer(dstAddress, pattern.getHostname());
                 if (!fromServer && !fromClient) {
                     // Packet not related to pattern, skip it.
                     continue;
@@ -65,7 +69,7 @@ public class FlowPatternFinder {
                 // TODO: this is strictly not sufficient to differentiate one TCP session from another, but should suffice for now.
                 Conversation conversation = fromClient ? new Conversation(srcAddress, srcPort, dstAddress, dstPort) :
                         new Conversation(dstAddress, dstPort, srcAddress, srcPort);
-                List<PcapPacket> listWrappedPacket = new ArrayList<>();
+                List<PcapPacket> listWrappedPacket = new ArrayList<>();               
                 listWrappedPacket.add(packet);
                 // Create new conversation entry, or append packet to existing.
                 connections.merge(conversation, listWrappedPacket, (v1, v2) -> {
@@ -82,6 +86,9 @@ public class FlowPatternFinder {
         } catch (EOFException eofe) {
             System.out.println("findFlowPattern: finished processing entire file");
             find(pattern);
+        } catch (UnknownHostException ex) {
+            System.out.println(); 
+            ex.printStackTrace();
         }
     }
 
index b323d84..d2867df 100644 (file)
@@ -1,6 +1,5 @@
 package edu.uci.iotproject;
 
-
 import org.pcap4j.core.*;
 import org.pcap4j.packet.*;
 import org.pcap4j.packet.DnsPacket;
@@ -26,11 +25,8 @@ public class Main {
 
 
     public static void main(String[] args) throws PcapNativeException, NotOpenException, EOFException, TimeoutException, UnknownHostException {
-        final String fileName = "/users/varmarken/Desktop/wlan1.local.dns.pcap";
-        List<DnsPacket> dnsPackets = extractDnsAnswerPackets(fileName);
-        Map<String, Set<String>> ipToHostnameMap = constructIpToHostnameMap(dnsPackets);
-//        ipToHostnameMap.forEach((k,v) -> System.out.println(String.format("%s => %s", k, v.toString())));
-
+        //final String fileName = "/users/varmarken/Desktop/wlan1.local.dns.pcap";
+        final String fileName = "/home/rtrimana/pcap_processing/smart_home_traffic/Code/Projects/SmartPlugDetector/pcap/wlan1.local.dns.pcap";
 
         // ====== Debug code ======
         PcapHandle handle;
@@ -39,257 +35,9 @@ public class Main {
         } catch (PcapNativeException pne) {
             handle = Pcaps.openOffline(fileName);
         }
-        FlowPatternFinder fpf = new FlowPatternFinder(ipToHostnameMap);
+        FlowPatternFinder fpf = new FlowPatternFinder();
         fpf.findFlowPattern(handle, FlowPattern.TP_LINK_LOCAL_ON);
 
         // ========================
     }
-
-    /**
-     * Opens a PCAP file and extracts all DNS reply packets with non-empty answer sections.
-     * @param pcapFileName The name of the PCAP file.
-     * @return A list of DNS reply packets.
-     * @throws PcapNativeException
-     * @throws NotOpenException
-     * @throws TimeoutException
-     */
-    private static List<DnsPacket> extractDnsAnswerPackets(String pcapFileName) throws PcapNativeException, NotOpenException, TimeoutException {
-        PcapHandle handle;
-        try {
-            handle = Pcaps.openOffline(pcapFileName, PcapHandle.TimestampPrecision.NANO);
-        } catch (PcapNativeException pne) {
-            handle = Pcaps.openOffline(pcapFileName);
-        }
-        // Apparently BPFs don't support "dns" protocol filter, so have to filter by port.
-        handle.setFilter("port 53", BpfProgram.BpfCompileMode.OPTIMIZE);
-        ArrayList<DnsPacket> result = new ArrayList<>();
-        try {
-            Packet packet;
-            while ((packet = handle.getNextPacketEx()) != null) {
-                DnsPacket dnsPacket = packet.get(DnsPacket.class);
-                // We only care about DNS answers.
-                if (dnsPacket != null && dnsPacket.getHeader().getAnswers().size() != 0) {
-                    result.add(dnsPacket);
-                }
-            }
-        } catch (EOFException eof) {
-            // (Note have to resort to EOFException as handle.getStats().getNumPacketsCaptured() only works on Windows)
-            // Clean up.
-            handle.close();
-        }
-        System.out.println(String.format("Found %d DNS answers", result.size()));
-        return result;
-    }
-
-    /**
-     * Based on the information found in a list of DNS replies, this method constructs a {@link Map} that maps from an
-     * IP to a {@link Set} of hostnames associated with that IP.
-     *
-     * @param dnsPackets A list of DNS <em>reply</em> packets.
-     * @return A {@link Map} that maps from an IP to a {@link Set} of hostnames associated with that IP
-     * @throws UnknownHostException If an IP found in a {@code DnsPacket} is of incorrect length.
-     */
-    private static Map<String, Set<String>> constructIpToHostnameMap(List<DnsPacket> dnsPackets) throws UnknownHostException {
-        HashMap<String, Set<String>> result = new HashMap<>();
-        for(DnsPacket dnsPacket : dnsPackets) {
-            // The hostname that this DNS reply provides answers for.
-            // TODO: safe to assume only one question?
-            String hostname = dnsPacket.getHeader().getQuestions().get(0).getQName().getName();
-            for(DnsResourceRecord answer : dnsPacket.getHeader().getAnswers()) {
-                // We only care about type A records
-                if (!answer.getDataType().equals(DnsResourceRecordType.A)) {
-                    continue;
-                }
-                // Sanity check. For some reason the hostname appears to be the empty string in the answer .
-                // We hence have to assume that all answers correspond to a single question that holds the hostname as part of its object tree.
-                // Therefore, if there are more questions in one query-reply exchange, we are in trouble.
-                if (!answer.getName().getName().equals("") && !answer.getName().getName().equals(hostname)) {
-                    throw new RuntimeException("[DNS parser] mismatch between hostname in question and hostname in answer");
-                }
-                // The IP in byte representation.
-                byte[] ipBytes = answer.getRData().getRawData();
-                // Convert to string representation.
-                String ip = Inet4Address.getByAddress(ipBytes).getHostAddress();
-                HashSet<String> hostnameSet = new HashSet<>();
-                hostnameSet.add(hostname);
-                // Update or insert depending on presence of key:
-                // Concat the existing set and the new set if ip already present as key,
-                // otherwise add an entry for ip pointing to new set.
-                result.merge(ip, hostnameSet, (v1, v2) -> { v1.addAll(v2); return v1; });
-            }
-        }
-        return result;
-    }
-
-
-
-//    /**
-//     * Private class properties
-//     */
-//    private Pcap pcap;
-//    private List<Pcap.Packet> listPacket;
-//    private Map<String, String> mapIPAddressToHostname;
-//
-//    /**
-//     * Private class constants
-//     */
-//    private static final int DNS_PORT = 53;
-//
-//    /**
-//     * Constructor
-//     *
-//     * @param   file    name of the analyzed PCAP file
-//     */
-//    public Main(String file) throws IOException {
-//
-//        pcap = Pcap.fromFile(file);
-//        listPacket = pcap.packets();
-//        mapIPAddressToHostname = new HashMap<String, String>();
-//    }
-//
-//
-//
-//
-//
-//    /**
-//     * Private method that maps DNS hostnames to their
-//     * respected IP addresses. This method iterates
-//     * through the List<Pcap.Packet>, gets DNS packets,
-//     * and gets the IP addresses associated with them.
-//     */
-//    private void mapHostnamesToIPAddresses() {
-//
-//        int counter = 1;
-//        for(Pcap.Packet packet : listPacket) {
-//            System.out.print("# " + counter++);
-//            // Check the packet type
-//            if (packet._root().hdr().network() == Pcap.Linktype.ETHERNET) {
-//                EthernetFrame ethFrame = (EthernetFrame) packet.body();
-//                if (ethFrame.etherType() == EthernetFrame.EtherTypeEnum.IPV4) {
-//                    Ipv4Packet ip4Packet = (Ipv4Packet) ethFrame.body();
-//
-//                    System.out.print(" - Protocol: " + ip4Packet.protocol());
-//                    if (ip4Packet.protocol() == Ipv4Packet.ProtocolEnum.UDP) {
-//                        // DNS is UDP port 53
-//                        UdpDatagram udpData = (UdpDatagram) ip4Packet.body();
-//                        System.out.print(" - Source Port: " + udpData.srcPort());
-//                        System.out.print(" - Dest Port: " + udpData.dstPort());
-//
-//                        // Source port 53 means this is DNS response
-//                        if (udpData.srcPort() == DNS_PORT) {
-//                            KaitaiStream dnsStream = new ByteBufferKaitaiStream(udpData.body());
-//                            DnsPacket dnsPacket = new DnsPacket(dnsStream);
-//                            ArrayList<DnsPacket.Query> queries = dnsPacket.queries();
-//                            ArrayList<DnsPacket.Answer> answers = dnsPacket.answers();
-//                            String strDomainName = new String();
-//                            for(DnsPacket.Query query : queries) {
-//                                System.out.print(" - Queries: ");
-//                                DnsPacket.DomainName domainName = query.name();
-//                                ArrayList<DnsPacket.Label> labels = domainName.name();
-//                                for(int i = 0; i < labels.size(); i++) {
-//                                    System.out.print(labels.get(i).name());
-//                                    strDomainName = strDomainName + labels.get(i).name();
-//                                    if(i < labels.size()-2) {
-//                                        System.out.print(".");
-//                                        strDomainName = strDomainName + ".";
-//                                    }
-//                                }
-//                                break;  // We are assuming that there is only one query
-//                            }
-//                            System.out.print(" - Answers " + answers.size());
-//                            for(DnsPacket.Answer answer : answers) {
-//                                System.out.print(" - TypeType: " + answer.type());
-//                                System.out.print(" - ClassType: " + answer.answerClass());
-//                                System.out.print("\n - Answers: ");
-//                                DnsPacket.Address address = answer.address();
-//                                if (answer.type() == DnsPacket.TypeType.A) {
-//                                    String strAnswer = new String();
-//                                    ArrayList<Integer> ipList = address.ip();
-//                                    for(int i = 0; i < ipList.size(); i++) {
-//                                        System.out.print(ipList.get(i));
-//                                        strAnswer = strAnswer + Integer.toString(ipList.get(i));
-//                                        if(i < ipList.size()-1) {
-//                                            System.out.print(".");
-//                                            strAnswer = strAnswer + ".";
-//                                        }
-//                                    }
-//                                    mapIPAddressToHostname.put(strAnswer, strDomainName);
-//                                }
-//                            }
-//                        }
-//                    }
-//                }
-//            }
-//            System.out.println();
-//        }
-////        for(Map.Entry<String, String> entry : mapIPAddressToHostname.entrySet()) {
-////            if (entry.getValue().equals("devs.tplinkcloud.com")) {
-////                System.out.println(entry.getKey() + " - " + entry.getValue());
-////            }
-////        }
-//        System.out.println("Total map size: " + mapIPAddressToHostname.size());
-//        System.out.println("Answer for 13.33.41.8: " + mapIPAddressToHostname.get("13.33.41.8"));
-//        System.out.println("Answer for 34.226.240.125: " + mapIPAddressToHostname.get("34.226.240.125"));
-//    }
-//
-//    /*private String cloudIPAddress(String hostName) {
-//        if (hostName.equals("events.tplinkra.com"))
-//            return "205.251.203.26";
-//        else
-//            return null;
-//    }*/
-//
-//    // TODO move to separate class
-//    // Add parameter that is the trace to be analyzed (most like the pcap library's representation of a flow)
-//    public String findPattern(Map<String, List<Integer>> hostnameToPacketLengths, String smartPlugIp) {
-//
-//        // No difference, output "Complete match"
-//        // If difference, output <Packet no, deviation from expected> for each packet
-//        return null;
-//    }
-//
-//    public static void main(String[] args) {
-//        System.out.println("it works");
-//
-//        //String file = "/home/rtrimana/pcap_processing/smart_home_traffic/Code/Projects/SmartPlugDetector/pcap/wlan1.local.dns.pcap";
-//        String file = "/home/rtrimana/pcap_processing/smart_home_traffic/Code/Projects/SmartPlugDetector/pcap/wlan1.remote.dns.pcap";
-//
-//        try {
-//            Main main = new Main(file);
-//            main.mapHostnamesToIPAddresses();
-//
-//            /*Pcap data = Pcap.fromFile(file);
-//            List<Pcap.Packet> listPacket = data.packets();
-//            System.out.println("Number of packets: " + listPacket.size());
-//            System.out.println("===================");
-//            for(Pcap.Packet packet : listPacket) {
-//                if (packet._root().hdr().network() == Pcap.Linktype.ETHERNET) {
-//                    EthernetFrame eFrame = (EthernetFrame) packet.body();
-//                    if (eFrame.etherType() == EthernetFrame.EtherTypeEnum.IPV4) {
-//                        Ipv4Packet ip4Packet = (Ipv4Packet) eFrame.body();
-//                        byte[] srcIp = ip4Packet.srcIpAddr();
-//                        byte[] dstIp = ip4Packet.dstIpAddr();
-//                        System.out.println("Byte length source: " + srcIp.length + " Byte length dest: " + dstIp.length);
-//                        System.out.print("Source: ");
-//                        for(int i = 0; i < srcIp.length; i++) {
-//                            System.out.print(Byte.toUnsignedInt(srcIp[i]));
-//                            if(i < srcIp.length-1)
-//                                System.out.print(".");
-//                        }
-//                        System.out.print(" - Dest: ");
-//                        for(int i = 0; i < dstIp.length; i++) {
-//                            System.out.print(Byte.toUnsignedInt(dstIp[i]));
-//                            if(i < dstIp.length-1)
-//                                System.out.print(".");
-//                            else
-//                                System.out.println("\n");
-//                        }
-//                    }
-//                }
-//            }*/
-//
-//        } catch (Exception e) {
-//            e.printStackTrace();
-//        }
-//    }
 }