风信网(ithov.com)原创文章：测试vsftpd中多个虚拟用户访问不同目录FTP服务器的功能，是在管理与维护FTP服务器是非常实用的一个技术，对于安全要求比较高的FTP来说，采用虚拟用户访问控制不同目录，能大大的提高FTP服务器系统的安全性，下面我们来详细的说明如何在vsftpd中配置多个虚拟用户访问不同目录FTP服务器的步骤。
本测试环境为：CentOS i686
如果你还没有安装vsftpd，可以使用如下命令进行安装：
[root@localhost /]# yum install vsftpd
详细安装请参阅《教你使用vsftpd架设Linux中的FTP：安装》
vsftpd安装完成之后的配置文件位于/etc/vsftpd/vsftpd.conf中，常用的配置项说明请参阅《教你使用vsftpd架设Linux中的FTP：配置》，如果你希望更加深入的研究与了解vsftpd.conf文件各配置的功能，请参阅《vsftpd.conf配置参数官方详解》。
配置虚拟用户及目录：
[root@localhost sunco]# cd /etc/vsftpd/
[root@localhost vsftpd]# cat logins.txt
ithov
123456
ftpuser
abcde
说明：单数行为用户名，偶数行为口令，
即：用户ithov 的口令为123456；用户ftp 的口令为abcde
下面使用db_load 命令生成口令库文件
[root@localhost vsftpd]# db_load -T -t hash -f logins.txt /etc/vsftpd/vsftpd_login.db
注意这里一定要用.db做为扩展名，此为数据库文件。
修改口令库文件的权限
[root@localhost vsftpd]# chmod 600 /etc/vsftpd/vsftpd_login.db
下面编辑生成虚拟用户所需的PAM 配置文件
[root@localhost vsftpd]# vi /etc/pam.d/vsftpd.vu
auth required /lib/security/pam_userdb.so db=/etc/vsftpd/vsftpd_login
account required /lib/security/pam_userdb.so db=/etc/vsftpd/vsftpd_login
注意：64位系统为/lib64目录
保存后退出vi。
注意：pam文件中db后面的数据库不能加扩展名
建立虚拟用户
[root@localhost vsftpd]# useradd virtual
注意这里不要设置口令
修改vsftpd.conf配置文件的内容：
[root@localhost vsftpd]# vi vsftpd.conf
添加如下内容：
user_config_dir=/etc/vsftpd/vsftpd_user_conf
#此为虚拟用户配置文件的目录
guest_enable=YES
#支持虚拟用户
guest_username=virtual
#映射虚拟用户名
pam_service_name=vsftpd.vu
#修改对应的pam认证文件
已经配置好的vsftpd.conf文件供大家参考
[root@localhost vsftpd]# cat 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).anonymous_enable=NO## Uncomment this to allow local users to log in.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.#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## The target log file can be vsftpd_log_file or xferlog_file.# This depends on setting xferlog_std_format parameterxferlog_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## The name of log file when xferlog_enable=YES and xferlog_std_format=YES# WARNING - changing this filename affects /etc/logrotate.d/vsftpd.logxferlog_file=/var/log/xferlog## Switches between logging into vsftpd_log_file and xferlog_file files.# NO writes to vsftpd_log_file, YES to xferlog_filexferlog_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 www.ithov.com 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().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. To listen on IPv4 and IPv6# sockets, you must run two copies of vsftpd with two configuration files.# Make sure, that one of the listen options is commented !!#listen_ipv6=YESuser_config_dir=/etc/vsftpd/vsftpd_user_confguest_enable=YESguest_username=virtualpam_service_name=vsftpd.vuuserlist_enable=YEStcp_wrappers=YES
建立虚拟用户文件夹
[root@localhost vsftpd]# mkdir /etc/vsftpd/vsftpd_user_conf
[root@localhost vsftpd]# cd /etc/vsftpd/vsftpd_user_conf
建立虚拟用户各自的权限与访问目录
[root@localhost vsftpd_user_conf]# vi ithov
local_root=/webservice/www
#ithov用户访问的目录为/webservice/www
anon_world_readable_only=YES
#用户可以浏览FTP目录和下载文件
anon_upload_enable=YES
#允许用户上传文件
anon_mkdir_write_enable=YES
#允许用户创建、删除目录
anon_other_write_enable=YES
#允许用户有其它读写权限，比如修改文件名称，删除文件等。
[root@localhost vsftpd_user_conf]# vi ftpuser
local_root=/webservice/ftpuser
# ftp用户访问的目录为/webservice/ftp
anon_world_readable_only=YES
anon_upload_enable=YES
anon_mkdir_write_enable=YES
anon_other_write_enable=YES
保存文件之后，我们重新启动vsftpd服务。
[root@localhost vsftpd_user_conf]# service vsftpd restart
关闭 vsftpd：[确定]
为 vsftpd 启动 vsftpd：[确定]
使用ftp工具登陆测试，可以正常使用啦！
如果你使用ftp工具登陆出现如下500 OOPS: cannot change directory:/home/ithov错误，请参阅《vsftpd中FTP登陆500 OOPS: cannot change directory:/home/ithov错误解决方法》