vsftpd虚拟用户及其权限配置

一、应用场景

使用虚拟用户实现vsftpd的权限控制
软件版本

~ # vsftpd -version
vsftpd: version 3.0.2
~ # 

二、配置过程

1、安装软件

yum install -y vsftpd db4

2、新建本地用户

新建一个本地用户，虚拟用户将映射到这个本地用户上.

useradd ftpuser

给这个本地用户配置密码

passwd ftpuser

3、修改vsftpd的配置文件

cat /etc/vsftpd/vsftpd.conf

# Example config file /etc/vsftpd/vsftpd.conf
#
# The default compiled in settings are fairly paranoid. This sample file
# loosens things up a bit, to make the ftp daemon more usable.
# Please see vsftpd.conf.5 for all compiled in defaults.
#
# READ THIS: This example file is NOT an exhaustive list of vsftpd options.
# Please read the vsftpd.conf.5 manual page to get a full idea of vsftpd's
# capabilities.
#
# Allow anonymous FTP? (Beware - allowed by default if you comment this out).
# 禁用匿名用户
anonymous_enable=NO
#
# Uncomment this to allow local users to log in.
# When SELinux is enforcing check for SE bool ftp_home_dir
local_enable=YES
#
# Uncomment this to enable any form of FTP write command.
write_enable=YES
#
# Default umask for local users is 077. You may wish to change this to 022,
# if your users expect that (022 is used by most other ftpd's)
local_umask=022
#
# Uncomment this to allow the anonymous FTP user to upload files. This only
# has an effect if the above global write enable is activated. Also, you will
# obviously need to create a directory writable by the FTP user.
# When SELinux is enforcing check for SE bool allow_ftpd_anon_write, allow_ftpd_full_access
#anon_upload_enable=YES
#
# Uncomment this if you want the anonymous FTP user to be able to create
# new directories.
#anon_mkdir_write_enable=YES
#
# Activate directory messages - messages given to remote users when they
# go into a certain directory.
dirmessage_enable=YES
#
# Activate logging of uploads/downloads.
xferlog_enable=YES
#
# Make sure PORT transfer connections originate from port 20 (ftp-data).
connect_from_port_20=YES
#
# If you want, you can arrange for uploaded anonymous files to be owned by
# a different user. Note! Using "root" for uploaded files is not
# recommended!
#chown_uploads=YES
#chown_username=whoever
#
# You may override where the log file goes if you like. The default is shown
# below.
#xferlog_file=/var/log/xferlog
#
# If you want, you can have your log file in standard ftpd xferlog format.
# Note that the default log file location is /var/log/xferlog in this case.
xferlog_std_format=YES
#
# You may change the default value for timing out an idle session.
#idle_session_timeout=600
#
# You may change the default value for timing out a data connection.
#data_connection_timeout=120
#
# It is recommended that you define on your system a unique user which the
# ftp server can use as a totally isolated and unprivileged user.
#nopriv_user=ftpsecure
#
# Enable this and the server will recognise asynchronous ABOR requests. Not
# recommended for security (the code is non-trivial). Not enabling it,
# however, may confuse older FTP clients.
#async_abor_enable=YES
#
# By default the server will pretend to allow ASCII mode but in fact ignore
# the request. Turn on the below options to have the server actually do ASCII
# mangling on files when in ASCII mode.
# Beware that on some FTP servers, ASCII support allows a denial of service
# attack (DoS) via the command "SIZE /big/file" in ASCII mode. vsftpd
# predicted this attack and has always been safe, reporting the size of the
# raw file.
# ASCII mangling is a horrible feature of the protocol.
#ascii_upload_enable=YES
#ascii_download_enable=YES
#
# You may fully customise the login banner string:
#ftpd_banner=Welcome to blah FTP service.
#
# You may specify a file of disallowed anonymous e-mail addresses. Apparently
# useful for combatting certain DoS attacks.
#deny_email_enable=YES
# (default follows)
#banned_email_file=/etc/vsftpd/banned_emails
#
# You may specify an explicit list of local users to chroot() to their home
# directory. If chroot_local_user is YES, then this list becomes a list of
# users to NOT chroot().
# (Warning! chroot'ing can be very dangerous. If using chroot, make sure that
# the user does not have write access to the top level directory within the
# chroot)
#chroot_local_user=YES
chroot_list_enable=YES
# (default follows)
#chroot_list_file=/etc/vsftpd/chroot_list
#
# You may activate the "-R" option to the builtin ls. This is disabled by
# default to avoid remote users being able to cause excessive I/O on large
# sites. However, some broken FTP clients such as "ncftp" and "mirror" assume
# the presence of the "-R" option, so there is a strong case for enabling it.
#ls_recurse_enable=YES
#
# When "listen" directive is enabled, vsftpd runs in standalone mode and
# listens on IPv4 sockets. This directive cannot be used in conjunction
# with the listen_ipv6 directive.
listen=YES
#
# This directive enables listening on IPv6 sockets. By default, listening
# on the IPv6 "any" address (::) will accept connections from both IPv6
# and IPv4 clients. It is not necessary to listen on *both* IPv4 and IPv6
# sockets. If you want that (perhaps because you want to listen on specific
# addresses) then you must run two copies of vsftpd with two configuration
# files.
# Make sure, that one of the listen options is commented !!
listen_ipv6=NOpam_service_name=vsftpd
userlist_enable=YES
tcp_wrappers=YES# 启用虚拟用户功能
guest_enable=YES# 指定虚拟用户的宿主用户，CentOS中已经有内置的ftp用户了,此处使用上面新建的ftpuser
guest_username=ftpuser# 配置虚拟用户路径，虚拟用户的配置文件放在该路径下
user_config_dir=/etc/vsftpd/vuser# 配置vsftpd日志
xferlog_enable=YES
xferlog_std_format=YES
xferlog_file=/var/log/xferlog
dual_log_enable=YES
vsftpd_log_file=/var/log/vsftpd.log
allow_writeable_chroot=YESpasv_enable=yes
pasv_min_port=2000
pasv_max_port=2020

4、新建虚拟用户目录

在vsftp.conf中，配置的虚拟用户目录为：user_config_dir=/etc/vsftpd/vuser，现在新建虚拟用户目录，每个虚拟用户的配置文件都放这个目录下

mkdir /etc/vsftpd/vuser

5、配置虚拟用户

（1）创建虚拟用户列表文件

cat /etc/vsftpd/virtual_users.txt

ftp1     #用户名
ftp1     #用户ftp1的密码，以此类推，创建了三个用户
ftp2
ftp2
ftp3
ftp3

（2）生成虚拟用户数据库

# 生成虚拟用户数据库文件
db_load -T -t hash -f /etc/vsftpd/virtual_users.txt /etc/vsftpd/virtual_users.db# 设置数据库文件权限
chmod 600 /etc/vsftpd/virtual_users.db

（3）配置pam认证

/etc/vsftpd/virtual_users是指文件/etc/vsftpd/virtual_users.db，.db要省略

cat /etc/pam.d/vsftpd

auth required pam_userdb.so db=/etc/vsftpd/virtual_users
account required pam_userdb.so db=/etc/vsftpd/virtual_users

（4）创建每个虚拟用户的文件目录

创建三个目录，作为三个ftp用户的文件根目录，因为这三个虚拟用户映射到了本地用户ftpuser，所以这三个虚拟用户的文件根目录的属主属组要改为ftpuser，否则会有权限问题

mkdir -p /data/ftp/{fpt1,fpt2,fpt3}
chown -R ftpuser:ftpuser /data/ftp/{ftp1,ftp2,ftp3}
chmod 755 /data/ftp/{ftp1,ftp2,ftp3}

（5)创建虚拟用户配置文件

ftp1的权限为：上传、下载
cat /etc/vsftpd/vuser/ftp1

local_root=/data/ftp/ftp1    #用户ftp1的文件根目录
# 上述挂载的磁盘，目录属主和属组必须为ftpuser,即映射的本地用户
write_enable=YES
anon_world_readable_only=NO
anon_upload_enable=YES
anon_mkdir_write_enable=YES
anon_other_write_enable=YES

ftp2的权限为：仅上传
cat /etc/vsftpd/vuser/ftp2

local_root=/data/ftp/ftp2
write_enable=YES
anon_world_readable_only=NO
download_enable=NO
anon_upload_enable=YES
anon_mkdir_write_enable=YES
anon_other_write_enable=YES

ftp3的权限为：仅下载
cat /etc/vsftpd/vuser/ftp3

local_root=/data/ftp/ftp3
write_enable=NO
anon_world_readable_only=NO
anon_upload_enable=NO
anon_mkdir_write_enable=NO
anon_other_write_enable=NO

6、重启服务

systemctl restart vsftpd

三、测试

在三个虚拟用户的文件根目录下新建测试文件

touch /data/ftp/fpt1/ftp1file
touch /data/ftp/fpt2/ftp2file
touch /data/ftp/fpt3/ftp3file

在客户端新建测试目录和文件

# pwd
/root/ftptset
# touch test.pdf
# ls
test.pdf

在客户端分别使用三个虚拟用户账号登录vsftpd服务器
ftp1（上传下载）:

[root@client:~/ftptset]
# lftp -u ftp1,ftp1 ftp://192.168.8.8
lftp ftp1@192.168.8.8:~> ls
-rw-------    1 1002     1002            0 Dec 29 11:52 1.txt
-rw-r--r--    1 0        0               0 Dec 29 13:23 ftp1file
-rw-r--r--    1 1002     1002            0 Dec 29 11:22 test
lftp ftp1@192.168.8.8:/> get ftp1file   # 下载文件
lftp ftp1@192.168.8.8:/> put test.pdf   # 上传文件
lftp ftp1@192.168.8.8:/> ls
-rw-------    1 1002     1002            0 Dec 29 11:52 1.txt
-rw-r--r--    1 0        0               0 Dec 29 13:23 ftp1file
-rw-r--r--    1 1002     1002            0 Dec 29 11:22 test
-rw-------    1 1002     1002            0 Dec 29 13:31 test.pdf
lftp ftp1@192.168.8.8:/>

ftp2（仅上传）：

# lftp -u ftp2,ftp2 ftp://192.168.8.8
lftp ftp2@192.168.8.8:~> ls
-rw-r--r--    1 0        0               0 Dec 29 13:23 ftp2file
lftp ftp2@192.168.8.8:/> put test.pdf
lftp ftp2@192.168.8.8:/> ls
-rw-r--r--    1 0        0               0 Dec 29 13:23 ftp2file
-rw-------    1 1002     1002            0 Dec 29 13:57 test.pdf
lftp ftp2@192.168.8.8:/> get ftp2file
get: Access failed: 550 Permission denied. (ftp2file)
lftp ftp2@192.168.8.8:/>

ftp3（仅下载）:

# lftp -u ftp3,ftp3 ftp://192.168.8.8
lftp ftp3@192.168.8.8:~> ls
-rw-r--r--    1 0        0               0 Dec 29 13:23 ftp3file
lftp ftp3@192.168.8.8:/> get ftp3file
lftp ftp3@192.168.8.8:/> put test.pdf
put: Access failed: 550 Permission denied. (test.pdf)
lftp ftp3@192.168.8.8:/>