/**
* 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.zookeeper.server.command;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.nio.ByteBuffer;
import java.util.HashMap;
import java.util.Map;
import java.util.HashSet;
import java.util.Set;
import java.util.Arrays;
/**
* This class contains constants for all the four letter commands
*/
public class FourLetterCommands {
/*
* See <a href="{@docRoot}/../../../docs/zookeeperAdmin.html#sc_zkCommands">
* Zk Admin</a>. this link is for all the commands.
*/
public final static int confCmd =
ByteBuffer.wrap("conf".getBytes()).getInt();
/*
* See <a href="{@docRoot}/../../../docs/zookeeperAdmin.html#sc_zkCommands">
* Zk Admin</a>. this link is for all the commands.
*/
public final static int consCmd =
ByteBuffer.wrap("cons".getBytes()).getInt();
/*
* See <a href="{@docRoot}/../../../docs/zookeeperAdmin.html#sc_zkCommands">
* Zk Admin</a>. this link is for all the commands.
*/
public final static int crstCmd =
ByteBuffer.wrap("crst".getBytes()).getInt();
/*
* See <a href="{@docRoot}/../../../docs/zookeeperAdmin.html#sc_zkCommands">
* Zk Admin</a>. this link is for all the commands.
*/
public final static int dirsCmd =
ByteBuffer.wrap("dirs".getBytes()).getInt();
/*
* See <a href="{@docRoot}/../../../docs/zookeeperAdmin.html#sc_zkCommands">
* Zk Admin</a>. this link is for all the commands.
*/
public final static int dumpCmd =
ByteBuffer.wrap("dump".getBytes()).getInt();
/*
* See <a href="{@docRoot}/../../../docs/zookeeperAdmin.html#sc_zkCommands">
* Zk Admin</a>. this link is for all the commands.
*/
public final static int enviCmd =
ByteBuffer.wrap("envi".getBytes()).getInt();
/*
* See <a href="{@docRoot}/../../../docs/zookeeperAdmin.html#sc_zkCommands">
* Zk Admin</a>. this link is for all the commands.
*/
public final static int getTraceMaskCmd =
ByteBuffer.wrap("gtmk".getBytes()).getInt();
/*
* See <a href="{@docRoot}/../../../docs/zookeeperAdmin.html#sc_zkCommands">
* Zk Admin</a>. this link is for all the commands.
*/
public final static int ruokCmd =
ByteBuffer.wrap("ruok".getBytes()).getInt();
/*
* See <a href="{@docRoot}/../../../docs/zookeeperAdmin.html#sc_zkCommands">
* Zk Admin</a>. this link is for all the commands.
*/
public final static int setTraceMaskCmd =
ByteBuffer.wrap("stmk".getBytes()).getInt();
/*
* See <a href="{@docRoot}/../../../docs/zookeeperAdmin.html#sc_zkCommands">
* Zk Admin</a>. this link is for all the commands.
*/
public final static int srvrCmd =
ByteBuffer.wrap("srvr".getBytes()).getInt();
/*
* See <a href="{@docRoot}/../../../docs/zookeeperAdmin.html#sc_zkCommands">
* Zk Admin</a>. this link is for all the commands.
*/
public final static int srstCmd =
ByteBuffer.wrap("srst".getBytes()).getInt();
/*
* See <a href="{@docRoot}/../../../docs/zookeeperAdmin.html#sc_zkCommands">
* Zk Admin</a>. this link is for all the commands.
*/
public final static int statCmd =
ByteBuffer.wrap("stat".getBytes()).getInt();
/*
* See <a href="{@docRoot}/../../../docs/zookeeperAdmin.html#sc_zkCommands">
* Zk Admin</a>. this link is for all the commands.
*/
public final static int wchcCmd =
ByteBuffer.wrap("wchc".getBytes()).getInt();
/*
* See <a href="{@docRoot}/../../../docs/zookeeperAdmin.html#sc_zkCommands">
* Zk Admin</a>. this link is for all the commands.
*/
public final static int wchpCmd =
ByteBuffer.wrap("wchp".getBytes()).getInt();
/*
* See <a href="{@docRoot}/../../../docs/zookeeperAdmin.html#sc_zkCommands">
* Zk Admin</a>. this link is for all the commands.
*/
public final static int wchsCmd =
ByteBuffer.wrap("wchs".getBytes()).getInt();
/*
* See <a href="{@docRoot}/../../../docs/zookeeperAdmin.html#sc_zkCommands">
* Zk Admin</a>. this link is for all the commands.
*/
public final static int mntrCmd = ByteBuffer.wrap("mntr".getBytes())
.getInt();
/*
* See <a href="{@docRoot}/../../../docs/zookeeperAdmin.html#sc_zkCommands">
* Zk Admin</a>. this link is for all the commands.
*/
public final static int isroCmd = ByteBuffer.wrap("isro".getBytes())
.getInt();
/*
* The control sequence sent by the telnet program when it closes a
* connection. Include simply to keep the logs cleaner (the server would
* close the connection anyway because it would parse this as a negative
* length).
*/
public final static int telnetCloseCmd = 0xfff4fffd;
private static final String ZOOKEEPER_4LW_COMMANDS_WHITELIST = "zookeeper.4lw.commands.whitelist";
private static final Logger LOG = LoggerFactory.getLogger(FourLetterCommands.class);
private static final Map<Integer, String> cmd2String = new HashMap<Integer, String>();
private static final Set<String> whiteListedCommands = new HashSet<String>();
private static boolean whiteListInitialized = false;
// @VisibleForTesting
public synchronized static void resetWhiteList() {
whiteListInitialized = false;
whiteListedCommands.clear();
}
/**
* Return the string representation of the specified command code.
*/
public static String getCommandString(int command) {
return cmd2String.get(command);
}
/**
* Check if the specified command code is from a known command.
*
* @param command The integer code of command.
* @return true if the specified command is known, false otherwise.
*/
public static boolean isKnown(int command) {
return cmd2String.containsKey(command);
}
/**
* Check if the specified command is enabled.
*
* In ZOOKEEPER-2693 we introduce a configuration option to only
* allow a specific set of white listed commands to execute.
* A command will only be executed if it is also configured
* in the white list.
*
* @param command The command string.
* @return true if the specified command is enabled
*/
public synchronized static boolean isEnabled(String command) {
if (whiteListInitialized) {
return whiteListedCommands.contains(command);
}
String commands = System.getProperty(ZOOKEEPER_4LW_COMMANDS_WHITELIST);
if (commands != null) {
String[] list = commands.split(",");
for (String cmd : list) {
if (cmd.trim().equals("*")) {
for (Map.Entry<Integer, String> entry : cmd2String.entrySet()) {
whiteListedCommands.add(entry.getValue());
}
break;
}
if (!cmd.trim().isEmpty()) {
whiteListedCommands.add(cmd.trim());
}
}
}
// It is sad that isro and srvr are used by ZooKeeper itself. Need fix this
// before deprecating 4lw.
if (System.getProperty("readonlymode.enabled", "false").equals("true")) {
whiteListedCommands.add("isro");
}
// zkServer.sh depends on "srvr".
whiteListedCommands.add("srvr");
whiteListInitialized = true;
LOG.info("The list of known four letter word commands is : {}", Arrays.asList(cmd2String));
LOG.info("The list of enabled four letter word commands is : {}", Arrays.asList(whiteListedCommands));
return whiteListedCommands.contains(command);
}
// specify all of the commands that are available
static {
cmd2String.put(confCmd, "conf");
cmd2String.put(consCmd, "cons");
cmd2String.put(crstCmd, "crst");
cmd2String.put(dirsCmd, "dirs");
cmd2String.put(dumpCmd, "dump");
cmd2String.put(enviCmd, "envi");
cmd2String.put(getTraceMaskCmd, "gtmk");
cmd2String.put(ruokCmd, "ruok");
cmd2String.put(setTraceMaskCmd, "stmk");
cmd2String.put(srstCmd, "srst");
cmd2String.put(srvrCmd, "srvr");
cmd2String.put(statCmd, "stat");
cmd2String.put(wchcCmd, "wchc");
cmd2String.put(wchpCmd, "wchp");
cmd2String.put(wchsCmd, "wchs");
cmd2String.put(mntrCmd, "mntr");
cmd2String.put(isroCmd, "isro");
cmd2String.put(telnetCloseCmd, "telnet close");
}
}