ACL：Access Control List  访问控制列表

1.  简介

0.概述

ACL 权限控制，使用：scheme:id:perm 来标识，主要涵盖 3 个方面：
　　权限模式（Scheme）：授权的策略
　　授权对象（ID）:授权的对象
　　权限（Permission）:授予的权限

其特性如下：
　　ZooKeeper的权限控制是基于每个znode节点的，需要对每个节点设置权限
　　每个znode支持设置多种权限控制方案和多个权限
　　子节点不会继承父节点的权限，客户端无权访问某节点，但可能可以访问它的子节点

例如:

setAcl /test2 ip:128.0.0.1:crwda

1.  scheme  采用何种方式授权

　　world：默认方式，相当于全部都能访问
　　auth：代表已经认证通过的用户(cli中可以通过addauth digest user:pwd 来添加当前上下文中的授权用户)
　　digest：即用户名:密码这种方式认证，这也是业务系统中最常用的。用 username:password 字符串来产生一个MD5串，然后该串被用来作为ACL ID。认证是通过明文发送username:password 来进行的，当用在ACL时，表达式为username:base64 ，base64是password的SHA1摘要的编码。
　　ip：使用客户端的主机IP作为ACL ID 。这个ACL表达式的格式为addr/bits ，此时addr中的有效位与客户端addr中的有效位进行比对。

2.  ID   给谁授予权限

　　授权对象ID是指，权限赋予的用户或者一个实体，例如：IP 地址或者机器。授权模式 schema 与 授权对象 ID 之间

3.  permission   授予什么权限

　　CREATE、READ、WRITE、DELETE、ADMIN 也就是 增、删、改、查、管理权限，这5种权限简写为crwda

注意:

　　这5种权限中，delete是指对子节点的删除权限，其它4种权限指对自身节点的操作权限

更详细的如下:

　　CREATE   c 可以创建子节点
　　DELETE   d 可以删除子节点（仅下一级节点）
　　READ       r 可以读取节点数据及显示子节点列表
　　WRITE     w 可以设置节点数据
　　ADMIN     a 可以设置节点访问控制列表权限

2.ACL 相关命令

getAcl        getAcl <path>     读取ACL权限
setAcl        setAcl <path> <acl>     设置ACL权限
addauth      addauth <scheme> <auth>     添加认证用户

3.测试zkCli设置权限

1.word方式

[zk: localhost:(CONNECTED) ] create /test1 test1-value

Created /test1

[zk: localhost:(CONNECTED) ] getAcl /test1  #创建的默认是所有用户都可以进行cdrwa

'world,'anyone

: cdrwa

[zk: localhost:(CONNECTED) ] setAcl /test1 world:anyone:acd   #修改为所有人可以acd

cZxid = 0x400000007

ctime = Tue Mar  :: CST

mZxid = 0x400000007

mtime = Tue Mar  :: CST

pZxid = 0x400000007

cversion =

dataVersion =

aclVersion =

ephemeralOwner = 0x0

dataLength =

numChildren =

[zk: localhost:(CONNECTED) ] getAcl /test1

'world,'anyone

: cda

2.IP的方式

[zk: localhost:(CONNECTED) ] create /test2 test2-value

Created /test2

[zk: localhost:(CONNECTED) ] setAcl /test2 ip:127.0.0.1:crwda   #修改此IP具有所有权限

cZxid = 0x400000009

ctime = Tue Mar  :: CST

mZxid = 0x400000009

mtime = Tue Mar  :: CST

pZxid = 0x400000009

cversion =

dataVersion =

aclVersion =

ephemeralOwner = 0x0

dataLength =

numChildren =

[zk: localhost:(CONNECTED) ] getAcl /test2

'ip,'127.0.0.1

: cdrwa

　当然可以设置IP的时候使用多个ip的方式，比如:

[zk: localhost:(CONNECTED) ] setAcl /t3 ip:192.168.0.164:cdwra,ip:127.0.0.1:cdwra

cZxid = 0x400000018

ctime = Tue Mar  :: CST

mZxid = 0x400000018

mtime = Tue Mar  :: CST

pZxid = 0x400000018

cversion =

dataVersion =

aclVersion =

ephemeralOwner = 0x0

dataLength =

numChildren =

[zk: localhost:(CONNECTED) ] getAcl /t3

'ip,'192.168.0.164

: cdrwa

'ip,'127.0.0.1

: cdrwa

3.  Auth

[zk: localhost:(CONNECTED) ] create /t4

Created /t4

[zk: localhost:(CONNECTED) ] addauth digest qlq:111222    #增加授权用户,明文用户名和密码

[zk: localhost:(CONNECTED) ] setAcl /t4 auth:qlq:cdwra　　#授予权限

cZxid = 0x40000001d

ctime = Tue Mar  :: CST

mZxid = 0x40000001d

mtime = Tue Mar  :: CST

pZxid = 0x40000001d

cversion =

dataVersion =

aclVersion =

ephemeralOwner = 0x0

dataLength =

numChildren =

[zk: localhost:(CONNECTED) ] getAcl /t4

'digest,'qlq:JWNEexxIoeVompjU7O5pZzTU+VQ=

: cdrwa

 如果重新连接之后获取会报没权限，需要添加授权用户:

[zk: localhost:(CONNECTED) ] get /t4

Authentication is not valid : /t4

[zk: localhost:(CONNECTED) ] addauth digest qlq:

[zk: localhost:(CONNECTED) ] get /t4

cZxid = 0x40000001d

ctime = Tue Mar  :: CST

mZxid = 0x40000001d

mtime = Tue Mar  :: CST

pZxid = 0x40000001d

cversion =

dataVersion =

aclVersion =

ephemeralOwner = 0x0

dataLength =

numChildren =

4. Digest

etAcl /test digest:用户名:密码:权限

　　密码是用户名和密码加密后的字符串。

(1)生成密码:sha1加密之后base64编码

package zd.dms.test;

import java.security.MessageDigest;

import java.security.NoSuchAlgorithmException;

import org.apache.commons.codec.binary.Base64;

public class Test {

    public static void main(String[] args) throws NoSuchAlgorithmException {

        String usernameAndPassword = "user:123456";

        byte digest[] = MessageDigest.getInstance("SHA1").digest(usernameAndPassword.getBytes());

        Base64 base64 = new Base64();

        String encodeToString = base64.encodeToString(digest);

        System.out.println(encodeToString);

    }

}

6DY5WhzOfGsWQ1XFuIyzxkpwdPo=

(2)设置权限

[zk: localhost:(CONNECTED) ] setAcl /t6  digest:user:6DY5WhzOfGsWQ1XFuIyzxkpwdPo=:crwda  #授权

cZxid = 0x400000028

ctime = Tue Mar  :: CST

mZxid = 0x400000028

mtime = Tue Mar  :: CST

pZxid = 0x400000028

cversion =

dataVersion =

aclVersion =

ephemeralOwner = 0x0

dataLength =

numChildren =

[zk: localhost:(CONNECTED) ] getAcl /t6

'digest,'user:6DY5WhzOfGsWQ1XFuIyzxkpwdPo=

: cdrwa

直接删除会不允许，也必须增加摘要之后才能删除

[zk: localhost:(CONNECTED) ] rmr /t6   #直接删除没权限

Authentication is not valid : /t6

[zk: localhost:(CONNECTED) ] addauth digest user:123456   #增加认证用户

[zk: localhost:(CONNECTED) ] rmr /t6

[zk: localhost:(CONNECTED) ] ls /

[t4, curator, test2, zookeeper, test1, t3]

5.Java原生的zookeperAPI的ACL

1.创建节点回顾

原来我们创建节点的时候如下:

package zookeper;

import java.io.IOException;

import java.util.concurrent.CountDownLatch;

import org.apache.zookeeper.CreateMode;

import org.apache.zookeeper.KeeperException;

import org.apache.zookeeper.WatchedEvent;

import org.apache.zookeeper.Watcher;

import org.apache.zookeeper.Watcher.Event.KeeperState;

import org.apache.zookeeper.ZooDefs;

import org.apache.zookeeper.ZooKeeper;

public class BaseAPI {

    private static ZooKeeper zoo;

    final static CountDownLatch connectedSignal = new CountDownLatch(1);

    public static ZooKeeper connect(String host) throws IOException, InterruptedException {

        zoo = new ZooKeeper(host, 5000, new Watcher() {

            public void process(WatchedEvent event) {

                if (event.getState() == KeeperState.SyncConnected) {

                    connectedSignal.countDown();

                }

            }

        });

        connectedSignal.await();

        return zoo;

    }

    public void close() throws InterruptedException {

        zoo.close();

    }

    public static void create(String path, byte[] data) throws KeeperException, InterruptedException {

        zoo.create(path, data, ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);

    }

    public static void main(String[] args) throws IOException, InterruptedException, KeeperException {

        final String path = "/t7";

        final ZooKeeper connect = connect("127.0.0.1:2181,127.0.0.1:2182,127.0.0.1:2183");

        connect.create(path, "777".getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);

        Thread.sleep(10 * 1000);

    }

}

可以看到create方法的第三个参数就是ACL集合,使用的是与zkCli方式一样的word:anyone:crwda 默认方式

如下:

        /**

         * This is a completely open ACL .

         */

     public final ArrayList<ACL> OPEN_ACL_UNSAFE = new ArrayList<ACL>(

                Collections.singletonList(new ACL(Perms.ALL, ANYONE_ID_UNSAFE)));

    public interface Perms {

        int READ = 1 << 0;

        int WRITE = 1 << 1;

        int CREATE = 1 << 2;

        int DELETE = 1 << 3;

        int ADMIN = 1 << 4;

        int ALL = READ | WRITE | CREATE | DELETE | ADMIN;

    }

    public interface Ids {

        public final Id ANYONE_ID_UNSAFE = new Id("world", "anyone");

        public final Id AUTH_IDS = new Id("auth", "");

        public final ArrayList<ACL> OPEN_ACL_UNSAFE = new ArrayList<ACL>(

                Collections.singletonList(new ACL(Perms.ALL, ANYONE_ID_UNSAFE)));

        public final ArrayList<ACL> CREATOR_ALL_ACL = new ArrayList<ACL>(

                Collections.singletonList(new ACL(Perms.ALL, AUTH_IDS)));

        public final ArrayList<ACL> READ_ACL_UNSAFE = new ArrayList<ACL>(

                Collections

                        .singletonList(new ACL(Perms.READ, ANYONE_ID_UNSAFE)));

    }

自己手动写一个采用IP的方式设置ACL的方法:

package zookeper;

import java.io.IOException;

import java.util.ArrayList;

import java.util.List;

import java.util.concurrent.CountDownLatch;

import org.apache.zookeeper.CreateMode;

import org.apache.zookeeper.KeeperException;

import org.apache.zookeeper.WatchedEvent;

import org.apache.zookeeper.Watcher;

import org.apache.zookeeper.Watcher.Event.KeeperState;

import org.apache.zookeeper.ZooDefs;

import org.apache.zookeeper.ZooDefs.Perms;

import org.apache.zookeeper.ZooKeeper;

import org.apache.zookeeper.data.ACL;

import org.apache.zookeeper.data.Id;

public class BaseAPI {

    private static ZooKeeper zoo;

    final static CountDownLatch connectedSignal = new CountDownLatch(1);

    public static ZooKeeper connect(String host) throws IOException, InterruptedException {

        zoo = new ZooKeeper(host, 5000, new Watcher() {

            public void process(WatchedEvent event) {

                if (event.getState() == KeeperState.SyncConnected) {

                    connectedSignal.countDown();

                }

            }

        });

        connectedSignal.await();

        return zoo;

    }

    public void close() throws InterruptedException {

        zoo.close();

    }

    public static void create(String path, byte[] data) throws KeeperException, InterruptedException {

        zoo.create(path, data, ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);

    }

    public static void main(String[] args) throws IOException, InterruptedException, KeeperException {

        final String path = "/t9";

        final ZooKeeper connect = connect("127.0.0.1:2181,127.0.0.1:2182,127.0.0.1:2183");

        // 创建ACL

        ACL acl = new ACL();

        // 创建Id，也可以设置构造方法传入scheme和id

        Id id = new Id("ip", "192.168.0.164");

        acl.setId(id);

        acl.setPerms(Perms.ALL);

        List<ACL> acls = new ArrayList<>();

        acls.add(acl);

        connect.create(path, "777".getBytes(), acls, CreateMode.PERSISTENT);

        Thread.sleep(10 * 1000);

    }

}

获取ACL:

package zookeper;

import java.io.IOException;

import java.util.ArrayList;

import java.util.List;

import java.util.concurrent.CountDownLatch;

import org.apache.zookeeper.CreateMode;

import org.apache.zookeeper.KeeperException;

import org.apache.zookeeper.WatchedEvent;

import org.apache.zookeeper.Watcher;

import org.apache.zookeeper.Watcher.Event.KeeperState;

import org.apache.zookeeper.ZooDefs;

import org.apache.zookeeper.ZooDefs.Perms;

import org.apache.zookeeper.ZooKeeper;

import org.apache.zookeeper.data.ACL;

import org.apache.zookeeper.data.Id;

public class BaseAPI {

    private static ZooKeeper zoo;

    final static CountDownLatch connectedSignal = new CountDownLatch(1);

    public static ZooKeeper connect(String host) throws IOException, InterruptedException {

        zoo = new ZooKeeper(host, 5000, new Watcher() {

            public void process(WatchedEvent event) {

                if (event.getState() == KeeperState.SyncConnected) {

                    connectedSignal.countDown();

                }

            }

        });

        connectedSignal.await();

        return zoo;

    }

    public void close() throws InterruptedException {

        zoo.close();

    }

    public static void create(String path, byte[] data) throws KeeperException, InterruptedException {

        zoo.create(path, data, ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);

    }

    public static void main(String[] args) throws IOException, InterruptedException, KeeperException {

        final String path = "/t9";

        final ZooKeeper connect = connect("127.0.0.1:2181,127.0.0.1:2182,127.0.0.1:2183");

        List<ACL> acls = connect.getACL("/t9", connect.exists("/t9", false));

        for (ACL acl : acls) {

            System.out.println(acl.getPerms());

            System.out.println(acl.getId());

        }

    }

}

结果：

31
'ip,'192.168.0.164

ckCli客户端进行验证:

[zk: localhost:(CONNECTED) ] getAcl /t9

'ip,'192.168.0.164

: cdrwa

补充:权限的计算方法:

<<：左移位，在低位处补0；  &与（AND），对两个整型操作数中对应位执行布尔代数，两个位都为1时输出1，否则0。

1

10

100

1000

10000

按位与之后是:11111  也就是十进制的31.

2.修改ACL

　　修改节点   /t10 节点的acl访问方式采用digest:user:111222

package zookeper;

import java.io.IOException;

import java.util.ArrayList;

import java.util.List;

import java.util.concurrent.CountDownLatch;

import org.apache.zookeeper.CreateMode;

import org.apache.zookeeper.KeeperException;

import org.apache.zookeeper.WatchedEvent;

import org.apache.zookeeper.Watcher;

import org.apache.zookeeper.Watcher.Event.KeeperState;

import org.apache.zookeeper.ZooDefs;

import org.apache.zookeeper.ZooDefs.Perms;

import org.apache.zookeeper.ZooKeeper;

import org.apache.zookeeper.data.ACL;

import org.apache.zookeeper.data.Id;

import org.apache.zookeeper.data.Stat;

public class BaseAPI {

    private static ZooKeeper zoo;

    final static CountDownLatch connectedSignal = new CountDownLatch(1);

    public static ZooKeeper connect(String host) throws IOException, InterruptedException {

        zoo = new ZooKeeper(host, 5000, new Watcher() {

            public void process(WatchedEvent event) {

                if (event.getState() == KeeperState.SyncConnected) {

                    connectedSignal.countDown();

                }

            }

        });

        connectedSignal.await();

        return zoo;

    }

    public void close() throws InterruptedException {

        zoo.close();

    }

    public static void create(String path, byte[] data) throws KeeperException, InterruptedException {

        zoo.create(path, data, ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);

    }

    public static void main(String[] args) throws IOException, InterruptedException, KeeperException {

        final String path = "/t10";

        final ZooKeeper connect = connect("127.0.0.1:2181,127.0.0.1:2182,127.0.0.1:2183");

        // 创建ACL

        ACL acl = new ACL();

        // 创建Id，也可以设置构造方法传入scheme和id

        Id id = new Id("digest", "user:6DY5WhzOfGsWQ1XFuIyzxkpwdPo=");

        acl.setId(id);

        acl.setPerms(Perms.ALL);

        List<ACL> acls = new ArrayList<>();

        acls.add(acl);

        // 修改ACL

        Stat setACL = connect.setACL(path, acls, connect.exists(path, false).getAversion());

        // 获取Acl

        System.out.println(connect.getACL(path, setACL));

    }

}

结果：

[31,s{'digest,'user:6DY5WhzOfGsWQ1XFuIyzxkpwdPo=}
]

zkCli客户端进行验证:

[zk: localhost:(CONNECTED) ] getAcl /t10

'digest,'user:6DY5WhzOfGsWQ1XFuIyzxkpwdPo=

: cdrwa

3.访问上面的节点会报错没权限

package zookeper;

import java.io.IOException;

import java.util.ArrayList;

import java.util.List;

import java.util.concurrent.CountDownLatch;

import org.apache.zookeeper.CreateMode;

import org.apache.zookeeper.KeeperException;

import org.apache.zookeeper.WatchedEvent;

import org.apache.zookeeper.Watcher;

import org.apache.zookeeper.Watcher.Event.KeeperState;

import org.apache.zookeeper.ZooDefs;

import org.apache.zookeeper.ZooDefs.Perms;

import org.apache.zookeeper.ZooKeeper;

import org.apache.zookeeper.data.ACL;

import org.apache.zookeeper.data.Id;

import org.apache.zookeeper.data.Stat;

public class BaseAPI {

    private static ZooKeeper zoo;

    final static CountDownLatch connectedSignal = new CountDownLatch(1);

    public static ZooKeeper connect(String host) throws IOException, InterruptedException {

        zoo = new ZooKeeper(host, 5000, new Watcher() {

            public void process(WatchedEvent event) {

                if (event.getState() == KeeperState.SyncConnected) {

                    connectedSignal.countDown();

                }

            }

        });

        connectedSignal.await();

        return zoo;

    }

    public void close() throws InterruptedException {

        zoo.close();

    }

    public static void create(String path, byte[] data) throws KeeperException, InterruptedException {

        zoo.create(path, data, ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);

    }

    public static void main(String[] args) throws IOException, InterruptedException, KeeperException {

        final String path = "/t10";

        final ZooKeeper connect = connect("127.0.0.1:2181,127.0.0.1:2182,127.0.0.1:2183");

        byte[] data = connect.getData(path, false, null);

        System.out.println(new String(data, "UTF-8"));

    }

}

结果：

log4j:WARN No appenders could be found for logger (org.apache.zookeeper.ZooKeeper).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
Exception in thread "main" org.apache.zookeeper.KeeperException$NoAuthException: KeeperErrorCode = NoAuth for /t10
at org.apache.zookeeper.KeeperException.create(KeeperException.java:113)
at org.apache.zookeeper.KeeperException.create(KeeperException.java:51)
at org.apache.zookeeper.ZooKeeper.getData(ZooKeeper.java:1212)
at org.apache.zookeeper.ZooKeeper.getData(ZooKeeper.java:1241)
at zookeper.BaseAPI.main(BaseAPI.java:42)

4.    解决办法:连接的connection增加用户信息

package zookeper;

import java.io.IOException;

import java.util.concurrent.CountDownLatch;

import org.apache.zookeeper.CreateMode;

import org.apache.zookeeper.KeeperException;

import org.apache.zookeeper.WatchedEvent;

import org.apache.zookeeper.Watcher;

import org.apache.zookeeper.Watcher.Event.KeeperState;

import org.apache.zookeeper.ZooDefs;

import org.apache.zookeeper.ZooKeeper;

public class BaseAPI {

    private static ZooKeeper zoo;

    final static CountDownLatch connectedSignal = new CountDownLatch(1);

    public static ZooKeeper connect(String host) throws IOException, InterruptedException {

        zoo = new ZooKeeper(host, 5000, new Watcher() {

            public void process(WatchedEvent event) {

                if (event.getState() == KeeperState.SyncConnected) {

                    connectedSignal.countDown();

                }

            }

        });

        connectedSignal.await();

        return zoo;

    }

    public void close() throws InterruptedException {

        zoo.close();

    }

    public static void create(String path, byte[] data) throws KeeperException, InterruptedException {

        zoo.create(path, data, ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);

    }

    public static void main(String[] args) throws IOException, InterruptedException, KeeperException {

        final String path = "/t10";

        final ZooKeeper connect = connect("127.0.0.1:2181,127.0.0.1:2182,127.0.0.1:2183");

        // 会话添加用户和密码信息

        connect.addAuthInfo("digest", "user:123456".getBytes());

        byte[] data = connect.getData(path, false, null);

        System.out.println(new String(data, "UTF-8"));

    }

}

结果：

10

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