hostage/src/de/tudarmstadt/informatik/hostage/ConnectionGuard.java

package de.tudarmstadt.informatik.hostage;

import de.tudarmstadt.informatik.hostage.logging.Logger;

public class ConnectionGuard {

	private final static ConnectionGuard INSTANCE = new ConnectionGuard();

	private ConnectionGuard() {
	}

	private final static long ONE_SECOND_IN_NANOSECONDS = 1000000000;

	private static long lastTimestamp = 0;
	private static String lastIP = "";
	private static String lastProtocol = "";

	public static void registerConnection(String protocol, String ip) {
		long timestamp = System.nanoTime();
		boolean firstConnection = (lastTimestamp == 0);
		boolean belowThreshold = ((timestamp - lastTimestamp) < ONE_SECOND_IN_NANOSECONDS);
		boolean sameIP = (lastIP == ip);
		boolean sameProtocol = (lastProtocol == protocol);
		if (!firstConnection && sameIP && belowThreshold && !sameProtocol) {
			Logger.logPortscan(Hostage.getContext(), System.currentTimeMillis(), ip);
		}
		lastTimestamp = timestamp;
		lastIP = ip;
		lastProtocol = protocol;
	}
}