ubuntu 14.04 下FTP服务器的搭建--锁定用户目录，解决vsftpd: refusing to run with writable root inside chroot()

FTP服务器的搭建，我要实现的需求是：

　　不允许匿名访问，因为我的机器不想让谁都能登录上来，随便获取文件，

　　需要锁定一个目录，因为在家里，我需要给媳妇下载一些电影 韩剧之类的东西，媳妇会来我机器下载，但是我不想让他随意操作我的东西。

　　万一删除我的配置文件，我就惨了（吐槽一下韩剧：媳妇问我，你都没看过韩剧怎么知道它不好看呢，我说：我没吃过屎 但是知道它一定不好吃！）

　　另外，需要本机也能访问，因为我要做一些关于FTP的测试。

　 不单独建立FTP用户，FTP也使用ubuntu桌面的用户进行登录和操作，

　　我还不希望FTP开始启动。

好了 我们开始安装，很简单。

　　

sudo apt-get install vsftpd 

30秒内估计就能安装完。

下面开始配置：

首先备份配置文件。

duoduo@ubuntu:/etc/init$ cd /etc/
duoduo@ubuntu:/etc$ sudo cp vsftpd.conf vsftpd.conf.old

接下来就是开始配置了，

咱们就针对需求来：

1. 不允许匿名访问，因为我的机器不想让谁都能登录上来，随便获取文件，

　　配置如下：

 　　23 anonymous_enable=NO

　　2.需要锁定一个目录，因为在家里，我需要给媳妇下载一些电影 韩剧之类的东西，

　　　媳妇会来我机器下载，但是我不想让他随意操作我的东西。

　　　万一删除我的配置文件，我就惨了

　　配置如下：

　　152 local_root=/home/duoduo/公共的/FTP共享文件
　　
   备注：[FTP共享文件] 这个文件夹是我新建出来的

　　另外，需要本机也能访问，因为我要做一些关于FTP的测试。

　　配置如下：

　　26 local_enable=YES

　 不单独建立FTP用户，FTP也使用ubuntu桌面的用户进行登录和操作，

　　配置如下：

　　120 #chroot_local_user=YES
　　121 chroot_list_enable=YES
　　122 # (default follows)
　　123 chroot_list_file=/etc/vsftpd.chroot_list

　　这里需要/etc/vsftpd.chroot_list 这个文件，如果没有请新建：
　　sudo gedit /etc/vsftpd.chroot_list
　　内容如下（例如我桌面的用户名为duoduo）：
　　

duoduo

　　其实就是把你的用户名写进去

　　我还不希望FTP开始启动。 一会单独说！

贴出我的配置文件。

 # Example config file /etc/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. for all compiled in defaults.
 #
 # READ THIS: This example file is NOT an exhaustive list of vsftpd options.
 # Please read the vsftpd.conf. manual page to get a full idea of vsftpd's
 # capabilities.
 #
 #
 # Run standalone?  vsftpd can run either from an inetd or as a standalone
 # daemon started from an initscript.
 listen=YES
 #
 # Run standalone with IPv6?
 # Like the listen parameter, except vsftpd will listen on an IPv6 socket
 # instead of an IPv4 one. This parameter and the listen parameter are mutually
 # exclusive.
 #listen_ipv6=YES
 #
 # Allow anonymous FTP? (Disabled by default)
 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 . You may wish to change this to ,
 # if your users expect that ( is used by most other ftpd's)
 #local_umask=
 #
 # 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
 #
 # If enabled, vsftpd will display directory listings with the time
 # in  your  local  time  zone.  The default is to display GMT. The
 # times returned by the MDTM FTP command are also affected by this
 # option.
 use_localtime=YES
 #
 # Activate logging of uploads/downloads.
 xferlog_enable=YES
 #
 # Make sure PORT transfer connections originate from port  (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/vsftpd.log
 #
 # 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=
 #
 # You may change the default value for timing out a data connection.
 #data_connection_timeout=
 #
 # 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 duoduo's 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 restrict local users to their home directories.  See the FAQ for
 # the possible risks in this before using chroot_local_user or
 # chroot_list_enable below.
 #chroot_local_user=YES
 #
 # 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
 #
 # Customization
 #
 # Some of vsftpd's settings don't fit the filesystem layout by
 # default.
 #
 # This option should be the name of a directory which is empty.  Also, the
 # directory should not be writable by the ftp user. This directory is used
 # as a secure chroot() jail at times vsftpd does not require filesystem
 # access.
 secure_chroot_dir=/var/run/vsftpd/empty
 #
 # This string is the name of the PAM service vsftpd will use.
 pam_service_name=vsftpd
 #
 # This option specifies the location of the RSA certificate to use for SSL
 # encrypted connections.
 rsa_cert_file=/etc/ssl/certs/ssl-cert-snakeoil.pem
 # This option specifies the location of the RSA key to use for SSL
 # encrypted connections.
 rsa_private_key_file=/etc/ssl/private/ssl-cert-snakeoil.key
 #
 local_root=/home/duoduo/公共的/FTP共享文件

现在可以重启FTP了。

duoduo@ubuntu:/etc$ sudo service vsftpd restart
vsftpd stop/waiting
vsftpd start/running, process 

OK 看到这些 证明配置文件没有问题，FTP启动了

下面直接访问FTP 看看：

duoduo@ubuntu:/etc$ ftp 127.0.0.1
Connected to 127.0.0.1.
 Welcome to Duoduo's FTP service.
Name (127.0.0.1:duoduo): duoduo
 Please specify the password.
Password:
 OOPS: vsftpd: refusing to run with writable root inside chroot()
Login failed.
 Service not available, remote server has closed connection
ftp> 

居然报了一个500的错误

vsftpd: refusing to run with writable root inside chroot()

。其实这里是需要特殊说明的，原因出在这里

120 #chroot_local_user=YES

121 chroot_list_enable=YES

122 # (default follows)

123 chroot_list_file=/etc/vsftpd.chroot_list

我们用

chroot_list_enable=YES 和 chroot_list_file=/etc/vsftpd.chroot_list配合使用，使得只有在vsftpd.chroot_list中配置的用户才能登录FTP。

对于这要的配置有一个特殊的要求，就是vsftpd.chroot_list里面配置的用户，对于前面local_root配置的目录不能有写的权限！

也就是/home/duoduo/公共的/FTP共享文件 这个文件夹 对于duoduo这个用户不能有写的权限，

我们为了额操作方便可以这么做：

 sudo chown -R root:root /home/duoduo/公共的/FTP共享文件/

这样，duoduo这个用户对于/home/duoduo/公共的/FTP共享文件没有写权限了，

现在重启FTP 重新登录看看：

duoduo@ubuntu:/etc$ ftp 127.0.0.1
Connected to 127.0.0.1.
 Welcome to duoduo's FTP service.
Name (127.0.0.1:duoduo): duoduo
 Please specify the password.
Password:
 Login successful.
Remote system type is UNIX.
Using binary mode to transfer files.
ftp>

OK  FTP 好了 可以登录了

但是我刚才 sudo chown -R root:root /home/duoduo/公共的/FTP共享文件/ 这个操作 还带来了一个麻烦。就是FTP共享文件在我桌面登录时，不能任意复制粘贴操作文件了，但是我还要必须保持duoduo用户对[FTP共享文件] 这个文件夹不可写。这该怎么办呢？

其实很简单，

cd /home/duoduo/公共的/FTP共享文件
sudo mkdir FTPFILES
sudo chown -R duoduo:duoduo FTPFILES

这样 就保持了 FTP共享文件 文件夹duoduo用户不可写，但duoduo用户用可以在桌面登录时任意操作文件了，只不过此时的随意范围在FTPFILES文件夹范围呢了。

这样基本FTP服务基本搭建完成了。

对了 忘记了一点。就是不让FTP服务开机启动。操作如下：

duoduo@ubuntu:/etc/init$ cd /etc/init/
duoduo@ubuntu:/etc/init$ sudo cp vsftpd.conf vsftpd.conf.old 

编辑配置文件

sudo gedit /etc/init/vsftpd.conf

将#start on runlevel [2345] or net-device-up IFACE!=lo 修改为start on runlevel [345] 如下：

#start on runlevel [] or net-device-up IFACE!=lo
start on runlevel []
stop on runlevel [!]

这次重启FTP 重启系统 彻底完成。

这里建议大家查一下：chroot_local_user  chroot_list_enable=YES chroot_list_file=/etc/vsftpd.chroot_list 相关的资料，这里面灵活性配置很高的。