Linux的用户

添加用户

---

添加删除用户

# useradd user
# passwd user
Changing password for user user.
New password:
BAD PASSWORD: it is too short
BAD PASSWORD: is too simple
Retype new password:
passwd: all authentication tokens updated successfully.
# userdel user

删除用户时，留下了主目录和邮件目录。需要清楚目录，需要参数“-r”

# userdel -r user1

用脚本方式添加多个用户

#!/bin/bash

# define vari
ADDUSER=$(which useradd)
PASSWD=$(which passwd)
USER=user
RES=

for ((i=; i<=; i++))
do
        $ADDUSER ${USER}${i} &> /dev/null
        RES=$(echo $?)
        if [ $RES -eq  ]
        then
                echo "user ${USER}${i} already exit."
                continue
        fi
        if [ $RES -eq  ]
        then
                echo "add user ${USER}${i} success."
        fi

        echo "${USER}${i}" | $PASSWD --stdin ${USER}${i} &> /dev/null
        RES=$(echo $?)

        if [ $RES -eq  ]
        then
                echo "update password for ${user}${i} success."
        fi
done

　　很多时候，需要添加的用户名往往没有规律，借助从一个包含用户名的文件里边读取用户名信息来完成用户名确认。增加输出信息：读取到用户名称，添加成功的用户，、未能添加的用户。

 #!/bin/bash
 # about return value.
 #
 #  without file username.

 # define vari
 ADDUSER=$(which useradd)
 CAT=$(which cat)
 ID=$(which id)
 PASSWD=$(which passwd)
 USER="./username"

 if [ -r $USER ]
 then
         echo "Will add $($CAT $USER | wc -l) users to this system."
         echo "$($CAT $USER)"
         echo "---------------"
 else
         echo "missing file username."
         exit
 fi

 for user in $(cat $USER)
 do
         $($ID $user &> /dev/null)
         RES=$(echo $?)
         if [ $RES ==  ]
         then
                 echo "user $user is exist."
         else
                 $ADDUSER $user &> /dev/null
                 if [ $(echo $?) -eq  ]
                 then
                         echo "user $user adds successful."

                         echo "${user}" | $PASSWD --stdin ${user} &> /dev/null

                         RES=$(echo $?)
                         if [ $RES -eq  ]
                         then
                                 echo "update password for ${user} success."
                         else
                                 echo "update password failed."
                         fi
                 else
                         echo "add user $user failed."
                 fi
         fi

 done

删除上边脚本建立的用户账户（前题条件：读取的文件“username”内容一致）

 #!/bin/bash
 # about return value.
 #
 #  without file username.

 # define vari
 DELUSER="$(which userdel)"
 CAT=$(which cat)
 ID=$(which id)
 PASSWD=$(which passwd)
 USER="./username"
 USERHOME="/home"
 MAILHOME="/var/mail"
 LS=$(which ls)

 if [ -r $USER ]
 then
         echo "Will delete $($CAT $USER | wc -l) users to this system."
         echo "$($CAT $USER)"
         echo "---------------"
 else
         echo "missing file username."
         exit
 fi

 for user in $(cat $USER)
 do
         $($ID $user &> /dev/null)
         RES=$(echo $?)
         if [ $RES ==  ]
         then
                 echo "will delete user $user."
                 $DELUSER -r $user &> /dev/null
                 RES=$(echo $?)
                 if [ $RES -eq  ]
                 then
                         echo "user $user delete successful."
                 else
                         echo "user $user delete failed."
                 fi
         else
                 echo "user $user is not exist."
         fi
 done

　　这里仅仅是成功运行了脚本，但是添加用户可能比这个脚本所预想的复杂。比如，建立一个用户，删除时没有带选项“-r”,而后又重新建立同名用户。再一次删除时，该账户下的某些目录无法删除，这个问题没有在该脚本里得到完美解决。

　

　　使用脚本的位置变量控制脚本运行结果。位置变量是“add”，完成用户添加；是“del”，完成用户删除。

 #!/bin/bash

 # define functions
 # adduser() add users from file username to the system, their password is same as user name.
 # deluser() delete users from file username from the system.

 adduser()
 {
 # about return value.
 #  without file username when add users.

 # define vari
 local ADDUSER=$(which useradd)
 local CAT=$(which cat)
 local ID=$(which id)
 local PASSWD=$(which passwd)
 local USER="./username"

 if [ -r $USER ]
 then
         echo "Will add $($CAT $USER | wc -l) users to this system."
         echo "$($CAT $USER)"
         echo "---------------"
 else
         echo "missing file username."
         exit
 fi

 for user in $(cat $USER)
 do
         $($ID $user &> /dev/null)
         RES=$(echo $?)
         if [ $RES ==  ]
         then
                 echo "user $user is exist."
         else
                 $ADDUSER $user &> /dev/null
                 if [ $(echo $?) -eq  ]
                 then
                         echo "user $user adds successful."

                         echo "${user}" | $PASSWD --stdin ${user} &> /dev/null

                         RES=$(echo $?)
                         if [ $RES -eq  ]
                         then
                                 echo "update password for ${user} success."
                         else
                                 echo "update password failed."
                         fi
                 else
                         echo "add user $user failed."
                 fi
         fi

 done
 }

 deluser()
 {
 # about return value.
 #  without file username when delete users.

 # define vari
 local DELUSER="$(which userdel)"
 local CAT=$(which cat)
 local ID=$(which id)
 local PASSWD=$(which passwd)
 local USER="./username"
 local USERHOME="/home"
 local MAILHOME="/var/mail"
 local LS=$(which ls)

 if [ -r $USER ]
 then
         echo "Will delete $($CAT $USER | wc -l) users from the system."
         echo "$($CAT $USER)"
         echo "---------------"
 else
         echo "missing file username."
         exit
 fi

 for user in $(cat $USER)
 do
         $($ID $user &> /dev/null)
         RES=$(echo $?)
         if [ $RES ==  ]
         then
                 echo "will delete user $user."
                 $DELUSER -r $user &> /dev/null
                 RES=$(echo $?)
                 if [ $RES -eq  ]
                 then
                         echo "user $user delete successful."
                 else
                         echo "user $user delete failed."
                 fi
         else
                 echo "user $user is not exist."
         fi
 done
 }

 # return value
 #  Command syntax error
 if [ $# -ne  ]
 then
         echo -e "Usage: user.sh ARG\n type: user.sh -h\n"
         exit
 fi

 if [ $ == 'add' ]
 then
         adduser
         exit
 fi

 if [ $ == 'del' ]
 then
         deluser
         exit
 fi

指定用户的特定信息

指定家目录：添加用户“sunny”，家目录是“/data01/hhh/”。

useradd -d /data01/hhh sunny

指定基础目录：添加用户“sunny”，家目录是“/data01/sunny”。

useradd -b /data01/ sunny

添加一个不让登陆系统的用户

useradd -s /sbin/nologin work

创建一个没有家目录的用户

useradd -M nginx
useradd -r nginx

为某个应用建立一个执行用户

useradd -r -s /sbin/nologin nginx

用户管理

---

* 手工完成用户的创建

* 使用命令完成用户的创建

手工完成用户的创建

group

manager:x:800:

passwd

view:x:810:800::/home/view:/bin/bash

dinglicom:x:811:800:/home/dinglicom:/bin/bash

shadow

view:!!:16358:0:99999:7:::

dinglicom:!!:16358:0:99999:7:::

“!!”表示锁定状态；需要创建密码

# passwd view
# passwd dinglicom

/home

# cd /home
# mkdir view
# mkdir dinglicom
# cp -R /etc/skel/* /home/view
# cp -R /etc/skel/* /home/dinglicom

# chown -R view:manager /home/view
# chown -R dinglicom:dinglicom /home/dinglicom
# chmod -R 700 /home/view
# chmod -R 700 /home/dinglicom

使用命令完成用户的创建

# groupadd -g  manager
# useradd -u  -d /home/view -c "Dinglicom viewers." -g manager -G ftp -s /bin/bash view
# useradd -u  -d /home/view -c "Dinglicom viewers." -g  -G ftp -s /bin/bash view
# passwd view
# groupmod -g  manager
# usermod -u  -g  view
# usermod -a http view
# id view
# usermod -L view
# cat /etc/shadow | grep view
# usermod -U view

useradd:

-u，指定UID（大于500）

-g，指定GID（需要是已存在的组；基本组）

-G，附件组（逗号隔开多个组）

# useradd -G root,ftp,http admin

-c，注释信息

-d，指定家目录

-s，指定shell路径（/etc/shells）

userdel：

-r，删除用户的时候，同时删除家目录

usermod：

-u，

-g，

-G -a，

-c，

-d，

id：

-n，不现实数字信息

-g，显示GID

-G，显示附件组信息

-u，显示UID

用户信息相关的文件

---

* group

* passwd

* shadow

* useradd

group

“组名:密码占位符:组ID:用户列表”

# cat /etc/group
root:x::
dba:x::oracle

1.1 组名

1.2 组密码（历史遗留）

1.3 组ID

1.4 组成员

passwd

# cat /etc/passwd
root:x:::root:/root:/bin/bash
oracle:x::::/home/oracle:/bin/bash

2.1 用户名

2.2 密码

2.3 用户ID

2.4 主要组ID

2.5 说明、注释（允许为空）

2.6 用户主目录

2.7 用户shell信息

shadow

（root的密码不是真实的）

# cat /etc/shadow
root:$$bu74FgD1S4fWkODOCyScBlTW1:::::::
oracle:!!:::::::

3.1 用户名

3.2 密码（加密算法、掺杂、最终密码特征码）

3.3 最后一次修改密码的天数（相对于生日来说的-19700101）

3.4 密码最小寿命、经过几天可以自行修改密码（0表示随时可以修改）

3.5 密码最大寿命、经过几天必须重新修改密码（设定密码到期时间）    （99999）

3.6 密码到期前几天开始提醒修改密码                （7）

3.7 密码到期后，账户被取消的天数

3.8 从创建账户开始，经过几天取消账户（默认为空，表示账户永不过期）

3.9 保留

生成配置文件

# cd /home/oracle
# ls -a
.  ..  .bash_logout  .bash_profile  .bashrc
# cd /etc/skel
# ls -a
.  ..  .bash_logout  .bash_profile  .bashrc

useradd

[root@hp430G2 default]# cat /etc/default/useradd
# useradd defaults file
GROUP=
HOME=/home
INACTIVE=-
EXPIRE=
SHELL=/bin/bash
SKEL=/etc/skel
CREATE_MAIL_SPOOL=yes

---

特殊权限

　　suid：

　　sgid：

　　sticky：