/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF 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 org.apache.tools.ant.taskdefs;
import java.net.Inet4Address;
import java.net.Inet6Address;
import java.net.InetAddress;
import java.net.NetworkInterface;
import java.util.Arrays;
import java.util.Enumeration;
import java.util.LinkedList;
import java.util.List;
import org.apache.tools.ant.BuildException;
import org.apache.tools.ant.Project;
import org.apache.tools.ant.Task;
/**
* Sets properties to the host provided, or localhost if no information is
* provided. The default properties are NAME, FQDN, ADDR4, ADDR6;
*
* @since Ant 1.8
* @ant.task category="utility"
*/
public class HostInfo extends Task {
private static final String DEF_REM_ADDR6 = "::";
private static final String DEF_REM_ADDR4 = "0.0.0.0"; //NOSONAR
private static final String DEF_LOCAL_ADDR6 = "::1";
private static final String DEF_LOCAL_ADDR4 = "127.0.0.1"; //NOSONAR
private static final String DEF_LOCAL_NAME = "localhost";
private static final String DEF_DOMAIN = "localdomain";
private static final String DOMAIN = "DOMAIN";
private static final String NAME = "NAME";
private static final String ADDR4 = "ADDR4";
private static final String ADDR6 = "ADDR6";
private String prefix = "";
private String host;
private InetAddress nameAddr;
private InetAddress best6;
private InetAddress best4;
private List<InetAddress> inetAddrs;
/**
* Set a prefix for the properties. If the prefix does not end with a "."
* one is automatically added.
*
* @param aPrefix
* the prefix to use.
* @since Ant 1.8
*/
public void setPrefix(String aPrefix) {
prefix = aPrefix;
if (!prefix.endsWith(".")) {
prefix += ".";
}
}
/**
* Set the host to be retrieved.
*
* @param aHost
* the name or the address of the host, data for the local host
* will be retrieved if omitted.
* @since Ant 1.8
*/
public void setHost(String aHost) {
host = aHost;
}
/**
* set the properties.
*
* @throws BuildException
* on error.
*/
@Override
public void execute() throws BuildException {
if (host == null || host.isEmpty()) {
executeLocal();
} else {
executeRemote();
}
}
private void executeLocal() {
try {
inetAddrs = new LinkedList<>();
Enumeration<NetworkInterface> interfaces = NetworkInterface.getNetworkInterfaces();
while (interfaces.hasMoreElements()) {
NetworkInterface currentif = interfaces.nextElement();
Enumeration<InetAddress> addrs = currentif.getInetAddresses();
while (addrs.hasMoreElements()) {
inetAddrs.add(addrs.nextElement());
}
}
selectAddresses();
if (nameAddr != null && hasHostName(nameAddr)) {
setDomainAndName(nameAddr.getCanonicalHostName());
} else {
setProperty(DOMAIN, DEF_DOMAIN);
setProperty(NAME, DEF_LOCAL_NAME);
}
if (best4 != null) {
setProperty(ADDR4, best4.getHostAddress());
} else {
setProperty(ADDR4, DEF_LOCAL_ADDR4);
}
if (best6 != null) {
setProperty(ADDR6, best6.getHostAddress());
} else {
setProperty(ADDR6, DEF_LOCAL_ADDR6);
}
} catch (Exception e) {
log("Error retrieving local host information", e, Project.MSG_WARN);
setProperty(DOMAIN, DEF_DOMAIN);
setProperty(NAME, DEF_LOCAL_NAME);
setProperty(ADDR4, DEF_LOCAL_ADDR4);
setProperty(ADDR6, DEF_LOCAL_ADDR6);
}
}
private boolean hasHostName(InetAddress addr) {
return !addr.getHostAddress().equals(addr.getCanonicalHostName());
}
private void selectAddresses() {
for (InetAddress current : inetAddrs) {
if (!current.isMulticastAddress()) {
if (current instanceof Inet4Address) {
best4 = selectBestAddress(best4, current);
} else if (current instanceof Inet6Address) {
best6 = selectBestAddress(best6, current);
}
}
}
nameAddr = selectBestAddress(best4, best6);
}
private InetAddress selectBestAddress(InetAddress bestSoFar,
InetAddress current) {
InetAddress best = bestSoFar;
if (best == null) {
// none selected so far, so this one is better.
best = current;
} else if (current == null || current.isLoopbackAddress()) {
// definitely not better than the previously selected address.
} else if (current.isLinkLocalAddress()) {
// link local considered better than loopback
if (best.isLoopbackAddress()) {
best = current;
}
} else if (current.isSiteLocalAddress()) {
// site local considered better than link local (and loopback)
// address with hostname resolved considered better than
// address without hostname
if (best.isLoopbackAddress()
|| best.isLinkLocalAddress()
|| (best.isSiteLocalAddress() && !hasHostName(best))) {
best = current;
}
} else {
// current is a "Global address", considered better than
// site local (and better than link local, loopback)
// address with hostname resolved considered better than
// address without hostname
if (best.isLoopbackAddress()
|| best.isLinkLocalAddress()
|| best.isSiteLocalAddress()
|| !hasHostName(best)) {
best = current;
}
}
return best;
}
private void executeRemote() {
try {
inetAddrs = Arrays.asList(InetAddress.getAllByName(host));
selectAddresses();
if (nameAddr != null && hasHostName(nameAddr)) {
setDomainAndName(nameAddr.getCanonicalHostName());
} else {
setDomainAndName(host);
}
if (best4 != null) {
setProperty(ADDR4, best4.getHostAddress());
} else {
setProperty(ADDR4, DEF_REM_ADDR4);
}
if (best6 != null) {
setProperty(ADDR6, best6.getHostAddress());
} else {
setProperty(ADDR6, DEF_REM_ADDR6);
}
} catch (Exception e) {
log("Error retrieving remote host information for host:" + host
+ ".", e, Project.MSG_WARN);
setDomainAndName(host);
setProperty(ADDR4, DEF_REM_ADDR4);
setProperty(ADDR6, DEF_REM_ADDR6);
}
}
private void setDomainAndName(String fqdn) {
int idx = fqdn.indexOf('.');
if (idx > 0) {
setProperty(NAME, fqdn.substring(0, idx));
setProperty(DOMAIN, fqdn.substring(idx+1));
} else {
setProperty(NAME, fqdn);
setProperty(DOMAIN, DEF_DOMAIN);
}
}
private void setProperty(String name, String value) {
getProject().setNewProperty(prefix + name, value);
}
}