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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