ҳ̸Ҳ̸ҳ Rabiza Ekel ҳ̸Ҳ̸ҳ
	: 18.119.106.176
	: 47.103.87.29 / bstest.wagas.com.cn
	: Linux Wagas-WebServer 3.10.0-1160.11.1.el7.x86_64 #1 SMP Fri Dec 18 16:34:56 UTC 2020 x86_64

: /usr/share/doc/vsftpd-3.0.2/EXAMPLE/INTERNET_SITE/ Upload File:

files >> /usr/share/doc/vsftpd-3.0.2/EXAMPLE/INTERNET_SITE/README.configuration

This example shows how you might set up a (possibly large) internet facing FTP site. The emphasis will be on security and performance. We will see how by integrating vsftpd with xinetd, we get a powerful combination. Step 1) Set up your xinetd configuration file. An example xinetd configuration file "vsftpd.xinetd" is supplied. To install it: cp vsftpd.xinetd /etc/xinetd.d/vsftpd Let's look at the important content in this file and see what it does: disable = no socket_type = stream wait = no This says that the service is active, and it is using standard TCP sockets. user = root server = /usr/local/sbin/vsftpd The server program /usr/local/sbin/vsftpd is used to handle incoming FTP requests, and the program is started as root (vsftpd will of course quickly drop as much privilege as possible). NOTE! Make sure that you have the vsftpd binary installed in /usr/local/sbin (or change the file path in the xinetd file). per_source = 5 instances = 200 For security, the maximum allowed connections from a single IP address is 5. The total maximum concurrent connections is 200. no_access = 192.168.1.3 As an example of how to ban certain sites from connecting, 192.168.1.3 will be denied access. banner_fail = /etc/vsftpd.busy_banner This is the file to display to users if the connection is refused for whatever reason (too many users, IP banned). Example of how to populate it: echo "421 Server busy, please try later." > /etc/vsftpd.busy_banner log_on_success += PID HOST DURATION log_on_failure += HOST This will log the IP address of all connection attempts - successful or not, along with the time. If an FTP server is launched for the connection, it's process ID and usage duration will be logged too. If you are using RedHat like me, this log information will appear in /var/log/secure. Step 2) Set up your vsftpd configuration file. An example file is supplied. Install it like this: cp vsftpd.conf /etc Let's example the contents of the file: # Access rights anonymous_enable=YES local_enable=NO write_enable=NO anon_upload_enable=NO anon_mkdir_write_enable=NO anon_other_write_enable=NO This makes sure the FTP server is in anonymous-only mode and that all write and upload permissions are disabled. Note that most of these settings are the same as the default values anyway - but where security is concerned, it is good to be clear. # Security anon_world_readable_only=YES connect_from_port_20=YES hide_ids=YES pasv_min_port=50000 pasv_max_port=60000 These settings, in order - Make sure only world-readable files and directories are served. - Originates FTP port connections from a secure port - so users on the FTP server cannot try and fake file content. - Hide the FTP server user IDs and just display "ftp" in directory listings. This is also a performance boost. - Set a 50000-60000 port range for passive connections - may enable easier firewall setup! # Features xferlog_enable=YES ls_recurse_enable=NO ascii_download_enable=NO async_abor_enable=YES In order, - Enables recording of transfer stats to /var/log/vsftpd.log - Disables "ls -R", to prevent it being used as a DoS attack. Note - sites wanting to be copied via the "mirror" program might need to enable this. - Disables downloading in ASCII mode, to prevent it being used as a DoS attack (ASCII downloads are CPU heavy). - Enables older FTP clients to cancel in-progress transfers. # Performance one_process_model=YES idle_session_timeout=120 data_connection_timeout=300 accept_timeout=60 connect_timeout=60 anon_max_rate=50000 In order, - Activates a faster "one process per connection" model. Note! To maintain security, this feature is only available on systems with capabilities - e.g. Linux kernel 2.4. - Boots off idle users after 2 minutes. - Boots off idle downloads after 5 minutes. - Boots off hung passive connects after 1 minute. - Boots off hung active connects after 1 minute. - Limits a single client to ~50kbytes / sec download speed. Step 3) Restart xinetd. (on RedHat) /etc/rc.d/init.d/xinetd restart If you run into problems, check: 1) Your /etc/xinetd.d directory only has one FTP service.

ҳ̸Ҳ̸ҳ Rabiza Ekel ҳ̸Ҳ̸ҳ