package org.moparscape.msc.gs.connection.filter;
import java.net.InetSocketAddress;
import java.net.SocketAddress;
import org.apache.mina.common.IoFilter;
import org.apache.mina.common.IoSession;
import org.apache.mina.filter.BlacklistFilter;
import org.moparscape.msc.gs.Instance;
import org.moparscape.msc.gs.config.Config;
import org.moparscape.msc.gs.event.SingleEvent;
import org.moparscape.msc.gs.util.Cache;
public class ConnectionFilter extends BlacklistFilter {
private Cache<String, Integer> connections = new Cache<String, Integer>(
Config.CONNECTION_THROTTLE_SIZE);
public void sessionCreated(IoFilter.NextFilter nextFilter, IoSession session) {
final SocketAddress sa = session.getRemoteAddress();
if (sa != null && sa instanceof InetSocketAddress) {
final InetSocketAddress a = (InetSocketAddress) sa;
final String host = a.getAddress().getHostAddress();
if (IPBanManager.isBlocked(host)) {
session.close();
return;
} else {
unblock(a.getAddress());
}
Integer val;
synchronized (connections) {
val = connections.get(host);
connections.put(host, val == null ? 1 : val + 1);
}
if (val != null && val + 1 >= Config.CONENCTION_THROTTLE_THRESHOLD) {
IPBanManager.throttle(host);
connections.remove(host);
block(a.getAddress());
session.close();
return;
}
}
super.sessionCreated(nextFilter, session);
}
public void sessionClosed(IoFilter.NextFilter nextFilter, IoSession session)
throws Exception {
final SocketAddress sa = session.getRemoteAddress();
if (sa != null && sa instanceof InetSocketAddress) {
final InetSocketAddress a = (InetSocketAddress) sa;
final Integer val;
synchronized (connections) {
val = connections.get(a.getAddress().getHostAddress());
}
if (val != null) {
if (Config.DELAY_REMOVAL > 0) {
Instance.getDelayedEventHandler().add(
new SingleEvent(null, Config.DELAY_REMOVAL) {
public void action() {
unblock(a);
}
});
} else {
unblock(a);
}
}
}
super.sessionClosed(nextFilter, session);
}
private void unblock(InetSocketAddress a) {
final String host = a.getAddress().getHostAddress();
final Integer val;
synchronized (connections) {
val = connections.get(host);
if (val == null) {
return;
}
if (val == 1) {
connections.remove(host);
} else {
connections.put(host, val - 1);
}
}
}
}