How to set up ProFTPD with SSL/TLS on Ubuntu Linux

This article describes setting up ProFTPD on Ubuntu Linux with SSL/TLS certificates.

FTP (File Transfer Protocol) is a popular way to transfer files between computers over a network. However, FTP communicates over an insecure channel, which means that someone with the right tool could intercept data between the server and the client reading it.

This is where SSL/TLS comes in. By enabling SSL/TLS on FTP, you add an extra layer of security that prevents data from being intercepted and read by unauthorized parties.

With SSL/TLS, even if the data is intercepted, they may still be unable to read the content, and that’s because of the extra security.

This article describes how to set up ProFTPD with SSL/TLS on Ubuntu Linux to ensure secure file transfers.

How to Install ProFTPD on Ubuntu Linux

First, you’ll want to install ProFTPD. To do that in Ubuntu Linux, run the commands below.

sudo apt update 
sudo apt-get install proftpd

It would be best to get a prompt during the installation with the message below: Select standalone.

 ProFTPD can be run either as a service from inetd, or as a standalone server. Each choice has its own 
 benefits. With only a few FTP                                                                           
 connections per day, it is probably better to run ProFTPD from inetd in order to save resouces.                                                                                                  
                                                                                                
 Run proftpd:                                                                                                                                                                            
                                 from inetd                                                            
                                 standalone 

After installing ProFTPD, the commands below can be used to stop, start, and enable the server service always to start up when the server boots.

sudo systemctl stop proftpd.service
sudo systemctl start proftpd.service
sudo systemctl enable proftpd.service

How to create a self-signed SSL/TLS certificate

Now that ProFTPD is installed run the commands below to generate a self-signed SSL/TLS certificate for the server.

The commands create a server key called proftpdserverkey. pem and store it in /etc/SSL/private and a certificate file called proftpdcertificate. pem in the /etc/SSL/certs.

sudo openssl req -x509 -nodes -newkey rsa:2048 -keyout /etc/ssl/private/proftpdserverkey.pem -out /etc/ssl/certs/proftpdcertificate.pem -days 365

After running the commands above, you’ll be prompted to answer a few questions about the certificate you’re generating… answer them and complete the process.

Generating a 2048 bit RSA private key
...+++
.+++
writing new private key to '/etc/ssl/private/proftpdserverkey.pem'
-----
You are about to be asked to enter information that will be incorporated
into your certificate request.
What you are about to enter is what is called a Distinguished Name or a DN.
There are quite a few fields but you can leave some blank
For some fields there will be a default value,
If you enter '.', the field will be left blank.
-----
Country Name (2 letter code) [AU]:US
State or Province Name (full name) [Some-State]:New York
Locality Name (eg, city) []:Brooklyn
Organization Name (eg, company) [Internet Widgits Pty Ltd]:Website for Students
Organizational Unit Name (eg, section) []:SSL Unit
Common Name (e.g. server FQDN or YOUR name) []:example.com
Email Address []:webmaster@example.com

VSFTP server will use the key and certificate created above.

How to configure ProFTPD to use SSL/TLS certificate

Now that you’ve generated the server private key and certificate files configure ProFTPD to use the SSL/TLS certificate created above. To do that, run the commands below to open the ProFTPD default configuration file.

sudo nano /etc/proftpd/tls.conf

Then, make the highlighted changes below so the server can communicate over SSL/TLS.

# This option specifies the location of the RSA certificate to use for SSL
# encrypted connections.
TLSRSACertificateFile /etc/ssl/certs/proftpdcertificate.pem
TLSRSACertificateKeyFile /etc/ssl/private/proftpdserverkey.pem
TLSEngine on
TLSLog /var/log/proftpd/tls.log
TLSProtocol SSLv23
TLSRequired on
TLSOptions NoCertRequest EnableDiags NoSessionReuseRequired
TLSVerifyClient off

Save your changes and restart the server.

Next, open the ProFTPD default configuration file and comment out this line to include the tools. Conf configurations.

sudo nano /etc/proftpd/proftpd.conf

Uncomment the line as shown below:

# This is used for FTPS connections
#
Include /etc/proftpd/tls.conf

Save the file exit

After adding the highlighted lines to the file, save it. Then, run the commands below to restart the ProFTPD server.

sudo systemctl restart proftpd

Now grab your favorite FTP client (FileZilla), set up a new site management site, and use FTP protocol with encryption with explicit FTP over TLS. Finally, type your username and password and connect.

You should be prompted with a certificate. Accept the certificate and continue. You may check the box at the bottom of the page to trust the certificate so you don’t get prompted in the future.

It would be best if you now were transferring files securely via SSL/TLS.

Enjoy!

Conclusion:

This post showed you how to install ProFTPD on Ubuntu Linux with SSL/TLS. Please use the comment form below if you find any errors above or have something to add.