1.ACL权限简介与开启

一.ACL权限是为了解决所有者/所属组/其他人三种身份不足的问题

二.查看分区ACL权限是否开启

dumpe2fs命令是查询指定分区详细文件系统信息的命令

 
dumpe2fs -h /dev/sda3
 

-h 仅显示超级块中信息,而不显示磁盘块组的详细信息

[root@izm5e2q95pbpe1hh0kkwoiz ~]# df -h Filesystem      Size  Used Avail Use% Mounted on /dev/vda1        40G   14G   25G  36% / devtmpfs        911M     0  911M   0% /dev tmpfs           920M     0  920M   0% /dev/shm tmpfs           920M  548K  920M   1% /run tmpfs           920M     0  920M   0% /sys/fs/cgroup tmpfs           184M     0  184M   0% /run/user/0 tmpfs           184M     0  184M   0% /run/user/1002 [root@izm5e2q95pbpe1hh0kkwoiz ~]# dumpe2fs -h /dev/vda1 dumpe2fs 1.42.9 (28-Dec-2013) Filesystem volume name:   <none> Last mounted on:          / Filesystem UUID:          eb448abb-3012-4d8d-bcde-94434d586a31 Filesystem magic number:  0xEF53 Filesystem revision #:    1 (dynamic) Filesystem features:      has_journal ext_attr resize_inode dir_index filetype needs_recovery extent flex_bg sparse_super large_file huge_file uninit_bg dir_nlink extra_isize Filesystem flags:         signed_directory_hash  Default mount options:    user_xattr acl Filesystem state:         clean Errors behavior:          Continue Filesystem OS type:       Linux Inode count:              2621440 Block count:              10485248 Reserved block count:     524262 Free blocks:              8958387 Free inodes:              2519237 First block:              0 Block size:               4096 Fragment size:            4096 Reserved GDT blocks:      1021 Blocks per group:         32768 Fragments per group:      32768 Inodes per group:         8192 Inode blocks per group:   512 RAID stride:              32639 Flex block group size:    16 Filesystem created:       Sun Oct 15 23:18:59 2017 Last mount time:          Tue Aug 14 10:15:43 2018 Last write time:          Tue Aug 14 18:15:42 2018 Mount count:              6 Maximum mount count:      -1 Last checked:             Wed Jun 27 22:35:57 2018 Check interval:           0 (<none>) Lifetime writes:          30 GB Reserved blocks uid:      0 (user root) Reserved blocks gid:      0 (group root) First inode:              11 Inode size:               256 Required extra isize:     28 Desired extra isize:      28 Journal inode:            8 First orphan inode:       1050280 Default directory hash:   half_md4 Directory Hash Seed:      2579899c-6862-4625-a8e6-425550384200 Journal backup:           inode blocks Journal features:         journal_incompat_revoke Journal size:             128M Journal length:           32768 Journal sequence:         0x006beeea Journal start:            22131

Default mount options: user_xattr acl显示支持acl

三.临时开启分区ACL权限

重新挂载根分区,并挂载加入acl权限

 
mount -o remount,acl /
 

四.永久开启分区ACL权限(一定要谨慎)

# 加入acl vim /etc/fstab UUID=eb448abb-3012-4d8d-bcde-94434d586a31 /                       ext4    defaults        1 1 修改为 UUID=eb448abb-3012-4d8d-bcde-94434d586a31 /                       ext4    defaults,acl        1 1  # 重新挂载文件系统或重新启动系统,使修改生效 mount -o remount /

2.查看和设定ACL权限

一.查看ACL命令

查看acl权限

 
getfacle 文件名
 

二.设定ACL权限的命令

 
setfacl 选项 文件名
 

三.给用户设定ACL权限和给组设定ACL权限

# 进入tmp目录 [root@izm5e2q95pbpe1hh0kkwoiz /]# cd /tmp  # 创建project目录 [root@izm5e2q95pbpe1hh0kkwoiz tmp]# mkdir project  # 查看是否创建 [root@izm5e2q95pbpe1hh0kkwoiz tmp]# ls Aegis-<Guid(5A2C30A2-A87D-490A-9281-6765EDAD7CBA)>  eternityz  hsperfdata_root  issue.soft  Japan  mysql.sock  php-cgi.sock  project  systemd-private-9255c5ee9ec84f5987c1d9ba485e177e-ntpd.service-eKcnmD  test.txt  # 添加用户zhangsan [root@izm5e2q95pbpe1hh0kkwoiz tmp]# useradd zhangsan  # 添加用户lisi [root@izm5e2q95pbpe1hh0kkwoiz tmp]# useradd lisi  # 添加组tgroup [root@izm5e2q95pbpe1hh0kkwoiz tmp]# groupadd tgroup  # 将zhangsan添加到组tgroup中 [root@izm5e2q95pbpe1hh0kkwoiz tmp]# gpasswd -a zhangsan tgroup Adding user zhangsan to group tgroup  # 将lisi添加到组tgroup中 [root@izm5e2q95pbpe1hh0kkwoiz tmp]# gpasswd -a lisi tgroup Adding user lisi to group tgroup  # 查看组内的用户(最后一行) [root@izm5e2q95pbpe1hh0kkwoiz tmp]# cat /etc/group root:x:0:eternity bin:x:1: daemon:x:2: sys:x:3: adm:x:4: tty:x:5: disk:x:6: lp:x:7: mem:x:8: kmem:x:9: wheel:x:10: cdrom:x:11: mail:x:12:postfix man:x:15: dialout:x:18: floppy:x:19: games:x:20: tape:x:30: video:x:39: ftp:x:50: lock:x:54: audio:x:63: nobody:x:99: users:x:100: utmp:x:22: utempter:x:35: ssh_keys:x:999: input:x:998: systemd-journal:x:190: systemd-network:x:192: dbus:x:81: polkitd:x:997: postdrop:x:90: postfix:x:89: chrony:x:996: sshd:x:74: ntp:x:38: tcpdump:x:72: nscd:x:28: screen:x:84: mysql:x:1000: www:x:1001: rabbitmq:x:995: eternity:x:1002: eternityz:x:1003: slocate:x:21: saslauth:x:76: mailnull:x:47: smmsp:x:51: zhangsan:x:1004: lisi:x:1005: tgroup:x:1006:zhangsan,lisi  # 将project目录的所属组更改为tgroup [root@izm5e2q95pbpe1hh0kkwoiz tmp]# chown root:tgroup project  # 将project目录的权限更改为770 [root@izm5e2q95pbpe1hh0kkwoiz tmp]# chmod 770 project  # 查看更改权限的project目录 [root@izm5e2q95pbpe1hh0kkwoiz tmp]# ll -d project drwxrwx--- 2 root tgroup 4096 Dec 10 17:00 project  # 增加试听学员st [root@izm5e2q95pbpe1hh0kkwoiz tmp]# useradd st  # 修改试听学员st的密码 [root@izm5e2q95pbpe1hh0kkwoiz tmp]# passwd st Changing password for user st. New password:  BAD PASSWORD: The password is shorter than 8 characters Retype new password:  passwd: all authentication tokens updated successfully.  # 给试听学员st设定ACL权限rx [root@izm5e2q95pbpe1hh0kkwoiz tmp]# setfacl -m u:st:rx project  # 查看ACL权限 [root@izm5e2q95pbpe1hh0kkwoiz tmp]# getfacl project # file: project # owner: root # group: tgroup user::rwx user:st:r-x  #st用户拥有rx权限 group::rwx mask::rwx other::---  # 切换到st用户 [root@izm5e2q95pbpe1hh0kkwoiz tmp]# su - st  # 进入/tmp/project目录 [st@izm5e2q95pbpe1hh0kkwoiz ~]$ cd /tmp/project  # 创建文件test.txt,提示没有权限 [st@izm5e2q95pbpe1hh0kkwoiz project]$ touch test.txt touch: cannot touch ‘test.txt’: Permission denied  # 退出st用户 [st@izm5e2q95pbpe1hh0kkwoiz project]$ exit logout  # 增加组tgroup2 [root@izm5e2q95pbpe1hh0kkwoiz tmp]# groupadd tgroup2  # 给组tgroup2设定ACL权限rwx [root@izm5e2q95pbpe1hh0kkwoiz tmp]# setfacl -m g:tgroup2:rwx project  # 查看ACL权限 [root@izm5e2q95pbpe1hh0kkwoiz tmp]# getfacl project # file: project # owner: root # group: tgroup user::rwx user:st:r-x # 用户st拥有ACL权限rx group::rwx group:tgroup2:rwx # 组tgroup2拥有ACL权限rwx mask::rwx other::---

有ACL权限和没ACL权限的文件夹

# 没有ACL权限的后面没有+号 [root@izm5e2q95pbpe1hh0kkwoiz tmp]# ll -d project drwxrwx--- 2 root tgroup 4096 Dec 10 17:00 project  [root@izm5e2q95pbpe1hh0kkwoiz tmp]# setfacl -m u:st:rx project  # 有ACL权限的后面带着+号 [root@izm5e2q95pbpe1hh0kkwoiz tmp]# ll -d project drwxrwx---+ 2 root tgroup 4096 Dec 10 17:00 project 

3.最大有效权限和删除ACL权限

一.最大有效权限mask

[root@izm5e2q95pbpe1hh0kkwoiz tmp]# getfacl project # file: project # owner: root # group: tgroup user::rwx user:st:r-x group::rwx group:st:rwx group:tgroup2:rwx mask::rwx other::---

 
mask是用来指定最大有效权限的.如果我给用户赋予了ACL权限,是需要和mask的权限"相与"才能得到用户的真正权限
 

修改mask的值

 
setfacl -m m:rx project
 

# 更改mask的值 [root@izm5e2q95pbpe1hh0kkwoiz tmp]# setfacl -m m:rx project  # 查询ACL权限 [root@izm5e2q95pbpe1hh0kkwoiz tmp]# getfacl project # file: project # owner: root # group: tgroup user::rwx user:st:r-x group::rwx                      #effective:r-x group:st:rwx                    #effective:r-x group:tgroup2:rwx               #effective:r-x mask::r-x other::---      mask的值只影响具有ACL权限的,不影响用户的权限     用户st的权限为rx     组st的ACL权限是rwx,但是实际生效的只是rx权限     组tgroup2的ACL权限是rwx,但是实际生效的是rx权限

二.删除ACL权限

删除指定用户的ACL权限

 
setfacl -x u:用户名 文件/文件夹
 

删除指定用户组的ACL权限

 
setfacl -x g:组名 文件/文件夹
 

# 之前的有组tgroup2的ACL权限 [root@izm5e2q95pbpe1hh0kkwoiz tmp]# getfacl project # file: project # owner: root # group: tgroup user::rwx user:st:r-x group::rwx                      #effective:r-x group:st:rwx                    #effective:r-x group:tgroup2:rwx               #effective:r-x mask::r-x other::---  # 移除组tgroup2的ACL权限 [root@izm5e2q95pbpe1hh0kkwoiz tmp]# setfacl -x g:tgroup2 project  # 再次查询,tgroup2的ACL权限没有了 [root@izm5e2q95pbpe1hh0kkwoiz tmp]# getfacl project # file: project # owner: root # group: tgroup user::rwx user:st:r-x group::rwx group:st:rwx mask::rwx other::---

删除文件或文件假的所有的ACL权限

 
sefacl -b 文件/文件夹
 

# 之前project目录的ACL权限 [root@izm5e2q95pbpe1hh0kkwoiz tmp]# getfacl project # file: project # owner: root # group: tgroup user::rwx user:st:r-x group::rwx group:st:rwx mask::rwx other::---  # 移除所有的ACL权限 [root@izm5e2q95pbpe1hh0kkwoiz tmp]# setfacl -b project  # 再次查询,ACL权限和mask都没有了 [root@izm5e2q95pbpe1hh0kkwoiz tmp]# getfacl project # file: project # owner: root # group: tgroup user::rwx group::rwx other::--- 

4.默认ACL权限和递归ACL权限

一.递归ACL权限

递归是父目录在设定ACL权限时,所有的子文件和子目录也会拥有相同的ACL权限

 
setfacl -m u:用户名:权限 -R 文件夹
 

# -R必须在后面,否则报错  # 给文件夹及下面的所有文件及文件夹设置ACL权限,运行此命令后,新建的文件不具备ACL权限

二.默认ACL权限

默认ACL权限的作用是如果给父目录设定了默认ACL权限,那么父目录中所有新建的子文件都会继承父目录的ACL权限

 
setfacl -m d:u:用户名:权限 文件夹
 

# 运行上面的命令之后,以后此文件夹下新建文件或文件夹都具备ACL权限

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