Download and install the VSFTPD package and XINETD package
# ipkg install vsftpd Package vsftpd (2.0.6-2) installed in root is up to date. Nothing to be done # ipkg install xinetd Package xinetd (2.3.14-7) installed in root is up to date. Nothing to be done #
Make a jailed user for outside access. We will poke a hole through our firewall to allow external FTP access.
adduser -h /home/ftpuser ftpuser passwd ftpuser
Designate this user as a JAILED user. /opt/etc/vsftpd.chroot_list
ftpuser
/opt/etc/vsftpd.conf
# Example config file /opt/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.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 # # 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. vsftpd_log_file=/opt/var/log/vsftpd.log # # If you want, you can have your log file in standard ftpd xferlog format #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=ftp # # 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 turning on ascii_download_enable enables malicious remote parties # to consume your I/O resources, by issuing the command "SIZE /big/file" in # ASCII mode. # These ASCII options are split into upload and download because you may wish # to enable ASCII uploads (to prevent uploaded scripts etc. from breaking), # without the DoS risk of SIZE and ASCII downloads. ASCII mangling should be # on the client anyway.. #ascii_upload_enable=YES #ascii_download_enable=YES # # You may fully customise the login banner string: ftpd_banner=Welcome to the NSLU2 vsftp daemon. # # 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=/opt/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_list_enable=YES # (default follows) chroot_list_file=/opt/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
Allow the XINETD super service to start-up FTP daemons for us.
/opt/etc/xinetd.d
service ftp
{
socket_type = stream
wait = no
user = root
server = /opt/sbin/vsftpd
server_args = /opt/etc/vsftpd.conf
nice = 10
disable = no
only_from = 0.0.0.0/0
}
Update: After having this configuration running and open to big bad internet I noticed a number of repeated attempts to hack into my FTP server. So I restricted it to only those networks where I know people may be accessing it from. It could be more restrictive but this seems to have done the trick for the moment.
#only_from = 0.0.0.0/0 only_from += .btcentralplus.com only_from += .btopenworld.com only_from += .virginmedia.com only_from += .ntl.com only_from += .optusnet.com.au only_from += .bigpond.com.au # and Locally too. only_from += 192.168.1.0/24