io.dropwizard.jetty.NetUtil Maven / Gradle / Ivy
/*
* Copyright 2012 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.dropwizard.jetty;
import java.io.IOException;
import java.net.InetAddress;
import java.net.NetworkInterface;
import java.net.SocketException;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Enumeration;
import java.util.List;
import java.util.Locale;
import java.util.concurrent.atomic.AtomicReference;
import static java.util.Objects.requireNonNull;
/**
* This class is taken from the Netty project, and all credit goes to them.
* It has been modified, to remove dependencies on other classes, and to convert to methods, rather than a
* static value.
*
* The {@link #getAllLocalIPs()} method was taken from the Apache Curator project
* which is also under the Apache 2.0 license.
*/
public class NetUtil {
public static final int DEFAULT_TCP_BACKLOG_WINDOWS = 200;
public static final int DEFAULT_TCP_BACKLOG_LINUX = 128;
public static final String TCP_BACKLOG_SETTING_LOCATION = "/proc/sys/net/core/somaxconn";
private static final AtomicReference LOCAL_IP_FILTER = new AtomicReference<>((nif, adr) ->
(adr != null) && !adr.isLoopbackAddress() && (nif.isPointToPoint() || !adr.isLinkLocalAddress())
);
/**
* The SOMAXCONN value of the current machine. If failed to get the value, {@code 200} is used as a
* default value for Windows or {@code 128} for others.
*/
public static int getTcpBacklog() {
return getTcpBacklog(getDefaultTcpBacklog());
}
/**
* The SOMAXCONN value of the current machine. If failed to get the value, defaultBacklog argument is
* used
*/
public static int getTcpBacklog(int tcpBacklog) {
// Taken from netty.
// As a SecurityManager may prevent reading the somaxconn file we wrap this in a privileged block.
//
// See https://github.com/netty/netty/issues/3680
return AccessController.doPrivileged((PrivilegedAction) () -> {
// Determine the default somaxconn (server socket backlog) value of the platform.
// The known defaults:
// - Windows NT Server 4.0+: 200
// - Linux and Mac OS X: 128
try {
return Integer.parseInt(new String(Files.readAllBytes(Paths.get(TCP_BACKLOG_SETTING_LOCATION)),
StandardCharsets.UTF_8).trim());
} catch (SecurityException | IOException | NumberFormatException | NullPointerException e) {
return tcpBacklog;
}
});
}
public static boolean isWindows() {
final boolean windows = System.getProperty("os.name", "").toLowerCase(Locale.US).contains("win");
return windows;
}
public static int getDefaultTcpBacklog() {
return isWindows() ? DEFAULT_TCP_BACKLOG_WINDOWS : DEFAULT_TCP_BACKLOG_LINUX;
}
/**
* Replace the default local ip filter used by {@link #getAllLocalIPs()}
*
* @param newLocalIpFilter the new local ip filter
*/
public static void setLocalIpFilter(LocalIpFilter newLocalIpFilter) {
requireNonNull(newLocalIpFilter);
LOCAL_IP_FILTER.set(newLocalIpFilter);
}
/**
* Return the current local ip filter used by {@link #getAllLocalIPs()}
*
* @return ip filter
*/
public static LocalIpFilter getLocalIpFilter() {
return requireNonNull(LOCAL_IP_FILTER.get());
}
/**
* based on http://pastebin.com/5X073pUc
*
*
* Returns all available IP addresses.
*
* In error case or if no network connection is established, we return
* an empty list here.
*
* Loopback addresses are excluded - so 127.0.0.1 will not be never
* returned.
*
* The "primary" IP might not be the first one in the returned list.
*
* @return Returns all IP addresses (can be an empty list in error case
* or if network connection is missing).
* @see getAllLocalIPs
* @see ServiceInstanceBuilder.java
* @throws SocketException errors
*/
public static Collection getAllLocalIPs() throws SocketException {
final List listAdr = new ArrayList<>();
final Enumeration nifs = NetworkInterface.getNetworkInterfaces();
if (nifs == null) {
return listAdr;
}
while (nifs.hasMoreElements()) {
final NetworkInterface nif = nifs.nextElement();
// We ignore subinterfaces - as not yet needed.
final Enumeration adrs = nif.getInetAddresses();
while (adrs.hasMoreElements()) {
final InetAddress adr = adrs.nextElement();
if (getLocalIpFilter().use(nif, adr)) {
listAdr.add(adr);
}
}
}
return listAdr;
}
}