src/main/java/net/pterodactylus/irc/connection/CtcpHandler.java

   1 package net.pterodactylus.irc.connection;
   2
   3 import static com.google.common.base.Optional.absent;
   4 import static com.google.common.base.Optional.fromNullable;
   5 import static com.google.common.base.Optional.of;
   6 import static java.lang.String.format;
   7 import static java.net.InetAddress.getByName;
   8 import static org.apache.log4j.Logger.getLogger;
   9
  10 import java.net.InetAddress;
  11 import java.net.UnknownHostException;
  12 import java.util.List;
  13
  14 import net.pterodactylus.irc.Connection;
  15 import net.pterodactylus.irc.Reply;
  16 import net.pterodactylus.irc.Source;
  17 import net.pterodactylus.irc.event.DccAcceptReceived;
  18 import net.pterodactylus.irc.event.DccSendReceived;
  19
  20 import com.google.common.base.Optional;
  21 import com.google.common.eventbus.EventBus;
  22 import com.google.common.primitives.Ints;
  23 import com.google.common.primitives.Longs;
  24 import org.apache.log4j.Logger;
  25
  26 /**
  27  * Handles all CTCP messages relevant to DCC transfers.
  28  *
  29  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  30  */
  31 public class CtcpHandler implements Handler {
  32
  33         private static final Logger logger = getLogger(CtcpHandler.class);
  34         private final EventBus eventBus;
  35         private final Connection connection;
  36
  37         public CtcpHandler(EventBus eventBus, Connection connection) {
  38                 this.eventBus = eventBus;
  39                 this.connection = connection;
  40         }
  41
  42         @Override
  43         public boolean willHandle(Reply reply) {
  44                 return (commandIs(reply, "PRIVMSG") || commandIs(reply, "NOTICE"))
  45                                 && messageIsCtcp(reply.parameters().get(1));
  46         }
  47
  48         private boolean commandIs(Reply reply, String command) {
  49                 return reply.command().equalsIgnoreCase(command);
  50         }
  51
  52         public static boolean messageIsCtcp(String message) {
  53                 return message.startsWith("\u0001") && message.endsWith("\u0001");
  54         }
  55
  56         @Override
  57         public void handleReply(Reply reply) {
  58                 List<String> parameters = reply.parameters();
  59                 String message = parameters.get(1);
  60                 Source source = reply.source().get();
  61                 handleCtcp(source, message);
  62         }
  63
  64         private void handleCtcp(Source client, String message) {
  65                 String[] messageWords = message.substring(1, message.length() - 1).split(" +");
  66                 String ctcpCommand = messageWords[0];
  67                 if (ctcpCommand.equalsIgnoreCase("DCC")) {
  68                         if (messageWords[1].equalsIgnoreCase("SEND")) {
  69                                 processDccSend(client, message, messageWords);
  70                         } else if (messageWords[1].equalsIgnoreCase("ACCEPT")) {
  71                                 processDccAccept(client, message, messageWords);
  72                         }
  73                 }
  74         }
  75
  76         private void processDccSend(Source client, String message,
  77                         String[] messageWords) {
  78                 Optional<DccSendInformation> dccSendInformation = parseDccSendInformation(messageWords);
  79                 if (dccSendInformation.isPresent()) {
  80                         eventBus.post(new DccSendReceived(connection, client,
  81                                         dccSendInformation.get().filename,
  82                                         dccSendInformation.get().internetAddress,
  83                                         dccSendInformation.get().port,
  84                                         dccSendInformation.get().size,
  85                                         dccSendInformation.get().token));
  86                 } else {
  87                         logger.warn(format("Received malformed DCC SEND: “%s”", message));
  88                 }
  89         }
  90
  91         private Optional<DccSendInformation> parseDccSendInformation(String[] messageWords) {
  92                 if (messageWords.length <5) {
  93                         return absent();
  94                 }
  95                 Optional<InetAddress> internetAddress = parseInetAddress(messageWords[3]);
  96                 Optional<Integer> port = fromNullable(Ints.tryParse(messageWords[4]));
  97                 long fileSize = (messageWords.length > 5) ? fromNullable(Longs.tryParse(messageWords[5])).or(-1L) : -1;
  98                 if (!internetAddress.isPresent() || !port.isPresent()) {
  99                         return absent();
 100                 }
 101                 String token = null;
 102                 if (messageWords.length > 6) {
 103                         token = messageWords[6];
 104                 }
 105                 return of(new DccSendInformation(messageWords[2], internetAddress.get(), port.get(), fileSize, token));
 106         }
 107
 108         private static class DccSendInformation {
 109
 110                 private final String filename;
 111                 private final InetAddress internetAddress;
 112                 private final int port;
 113                 private final long size;
 114                 private final String token;
 115
 116                 private DccSendInformation(String filename, InetAddress internetAddress, int port, long size, String token) {
 117                         this.filename = filename;
 118                         this.internetAddress = internetAddress;
 119                         this.port = port;
 120                         this.size = size;
 121                         this.token = token;
 122                 }
 123
 124         }
 125
 126         private Optional<InetAddress> parseInetAddress(String ip) {
 127                 Long ipNumber = Longs.tryParse(ip);
 128                 if (ipNumber == null) {
 129                         return absent();
 130                 }
 131
 132                 StringBuilder hostname = new StringBuilder(15);
 133                 hostname.append((ipNumber >>> 24) & 0xff).append('.');
 134                 hostname.append((ipNumber >>> 16) & 0xff).append('.');
 135                 hostname.append((ipNumber >>> 8) & 0xff).append('.');
 136                 hostname.append(ipNumber & 0xff);
 137                 try {
 138                         return of(getByName(hostname.toString()));
 139                 } catch (UnknownHostException uhe1) {
 140                         return absent();
 141                 }
 142         }
 143
 144         private void processDccAccept(Source client, String message,
 145                         String[] messageWords) {
 146                 Optional<DccAcceptInformation> dccAcceptInformation = parseDccAcceptInformation(messageWords);
 147                 if (dccAcceptInformation.isPresent()) {
 148                         eventBus.post(new DccAcceptReceived(connection, client,
 149                                         dccAcceptInformation.get().filename,
 150                                         dccAcceptInformation.get().port,
 151                                         dccAcceptInformation.get().position));
 152                 } else {
 153                         logger.warn(format("Received malformed DCC ACCEPT: “%s”", message));
 154                 }
 155         }
 156
 157         private Optional<DccAcceptInformation> parseDccAcceptInformation(
 158                         String[] messageWords) {
 159                 if (messageWords.length < 4) {
 160                         return absent();
 161                 }
 162                 Optional<Integer> port = fromNullable(Ints.tryParse(messageWords[3]));
 163                 long position = (messageWords.length > 4) ? fromNullable(
 164                                 Longs.tryParse(messageWords[4])).or(-1L) : -1;
 165                 if (!port.isPresent()) {
 166                         return absent();
 167                 }
 168                 return of(new DccAcceptInformation(messageWords[2], port.get(), position));
 169         }
 170
 171         private static class DccAcceptInformation {
 172
 173                 private final String filename;
 174                 private final int port;
 175                 private final long position;
 176
 177                 private DccAcceptInformation(String filename, int port, long position) {
 178                         this.filename = filename;
 179                         this.port = port;
 180                         this.position = position;
 181                 }
 182
 183         }
 184
 185 }