/*
* Copyright 2011 The Netty Project
*
* The Netty Project licenses this file to you under the Apache License,
* version 2.0 (the "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*/
package io.netty.handler.ipfilter;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
import io.netty.channel.ChannelEvent;
import io.netty.channel.ChannelHandler.Sharable;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelState;
import io.netty.channel.ChannelStateEvent;
/**
* Handler that block any new connection if there are already a currently active
* channel connected with the same InetAddress (IP).<br>
* <br>
* <p/>
* Take care to not change isBlocked method except if you know what you are doing
* since it is used to test if the current closed connection is to be removed
* or not from the map of currently connected channel.
*/
@Sharable
public class OneIpFilterHandler extends IpFilteringHandlerImpl {
/** HashMap of current remote connected InetAddress */
private final ConcurrentMap<InetAddress, Boolean> connectedSet = new ConcurrentHashMap<InetAddress, Boolean>();
@Override
protected boolean accept(ChannelHandlerContext ctx, ChannelEvent e, InetSocketAddress inetSocketAddress)
throws Exception {
InetAddress inetAddress = inetSocketAddress.getAddress();
if (connectedSet.containsKey(inetAddress)) {
return false;
}
connectedSet.put(inetAddress, Boolean.TRUE);
return true;
}
@Override
public void handleUpstream(ChannelHandlerContext ctx, ChannelEvent e) throws Exception {
super.handleUpstream(ctx, e);
// Try to remove entry from Map if already exists
if (e instanceof ChannelStateEvent) {
ChannelStateEvent evt = (ChannelStateEvent) e;
if (evt.getState() == ChannelState.CONNECTED) {
if (evt.getValue() == null) {
// DISCONNECTED but was this channel blocked or not
if (isBlocked(ctx)) {
// remove inetsocketaddress from set since this channel was not blocked before
InetSocketAddress inetSocketAddress = (InetSocketAddress) e.getChannel().getRemoteAddress();
connectedSet.remove(inetSocketAddress.getAddress());
}
}
}
}
}
}