We can create a self-signed key and certificate pair with OpenSSL in a single command :

sudo openssl req -x509 -nodes -days 365 -newkey rsa:2048 -keyout  /etc/ssl/private/apache-selfsigned.key -out /etc/ssl/certs/apache-selfsigned.crt

You will be asked a series of questions. Before we go over that, let’s take a look at what is happening in the command we are issuing:

Output
Country Name (2 letter code) [AU]:US
State or Province Name (full name) [Some-State]:New York
Locality Name (eg, city) []:New York City
Organization Name (eg, company) [Internet Widgits Pty Ltd]:Bouncy Castles, Inc.
Organizational Unit Name (eg, section) []:Ministry of Water Slides
Common Name (e.g. server FQDN or YOUR name) []:server_IP_address
Email Address []:admin@your_domain.com

Both of the files you created will be placed in the appropriate subdirectories under /etc/ssl.

We have created our key and certificate files under the /etc/ssl directory. Now we just need to modify our Apache configuration to take advantage of these.

We will make a few adjustments to our configuration :

1. We will create a configuration snippet to specify strong default SSL settings.
2. We will modify the included SSL Apache Virtual Host file to point to our generated SSL certificates.(Recommended)
3. We will modify the unencrypted Virtual Host file to automatically redirect requests to the encrypted Virtual Host.

When we are finished, we should have a secure SSL configuration.

First, we will create an Apache configuration snippet to define some SSL settings. This will set Apache up with a strong SSL cipher suite and enable some advanced features that will help keep our server secure. The parameters we will set can be used by any Virtual Hosts enabling SSL.

Create a new snippet in the /etc/apache2/conf-available directory. We will name the file ssl-params.conf to make its purpose clear:

sudo nano /etc/apache2/conf-available/ssl-params.conf

Paste the following configuration into the ssl-params.conf file we opened:

SSLCipherSuite EECDH+AESGCM:EDH+AESGCM:AES256+EECDH:AES256+EDH
SSLProtocol All -SSLv2 -SSLv3 -TLSv1 -TLSv1.1
SSLHonorCipherOrder On
# Disable preloading HSTS for now.  You can use the commented out header line that includes
# the "preload" directive if you understand the implications.
# Header always set Strict-Transport-Security "max-age=63072000; includeSubDomains; preload"
Header always set X-Frame-Options DENY
Header always set X-Content-Type-Options nosniff
# Requires Apache >= 2.4
SSLCompression off
SSLUseStapling on
SSLStaplingCache "shmcb:logs/stapling-cache(150000)"
# Requires Apache >= 2.4.11
SSLSessionTickets Off

Save and close the file when you are finished.

Modifying the Default Apache SSL Virtual Host File

Next, let’s modify /etc/apache2/sites-available/default-ssl.conf, the default Apache SSL Virtual Host file. If you are using a different server block file, substitute its name in the commands below.

Before we go any further, let’s back up the original SSL Virtual Host file :

sudo cp /etc/apache2/sites-available/default-ssl.conf /etc/apache2/sites-available/default-ssl.conf.bak

Now, open the SSL Virtual Host file to make adjustments :

sudo nano /etc/apache2/sites-available/default-ssl.conf

Inside, with most of the comments removed, the Virtual Host block should look something like this by default:

/etc/apache2/sites-available/default-ssl.conf

<IfModule mod_ssl.c>
        <VirtualHost _default_:443>
                SServerAdmin webmaster@localhost
 
                DocumentRoot /var/www/html
 
                ErrorLog ${APACHE_LOG_DIR}/error.log
                CustomLog ${APACHE_LOG_DIR}/access.log combined
 
                SSLEngine on
 
                SSLCertificateFile      /etc/ssl/certs/ssl-cert-snakeoil.pem
                SSLCertificateKeyFile /etc/ssl/private/ssl-cert-snakeoil.key
 
                <FilesMatch "\.(cgi|shtml|phtml|php)$">
                                SSLOptions +StdEnvVars
                </FilesMatch>
                <Directory /usr/lib/cgi-bin>
                                SSLOptions +StdEnvVars
                </Directory>
 
        </VirtualHost>
</IfModule>

We will be making some minor adjustments to the file. We will set the normal things we’d want to adjust in a Virtual Host file (ServerAdmin email address, ServerName, etc.), and adjust the SSL directives to point to our certificate and key files. Again, if you’re using a different document root, be sure to update the DocumentRoot directive.

After making these changes, your server block should look similar to this:

/etc/apache2/sites-available/default-ssl.conf

<IfModule mod_ssl.c>
        <VirtualHost _default_:443>
                ServerAdmin your_email@example.com
                ServerName server_domain_or_IP
 
                DocumentRoot /var/www/html
 
                ErrorLog ${APACHE_LOG_DIR}/error.log
                CustomLog ${APACHE_LOG_DIR}/access.log combined
 
                SSLEngine on
 
                SSLCertificateFile      /etc/ssl/certs/apache-selfsigned.crt
                SSLCertificateKeyFile /etc/ssl/private/apache-selfsigned.key
 
                <FilesMatch "\.(cgi|shtml|phtml|php)$">
                                SSLOptions +StdEnvVars
                </FilesMatch>
                <Directory /usr/lib/cgi-bin>
                                SSLOptions +StdEnvVars
                </Directory>
 
        </VirtualHost>
</IfModule>

Save and close the file when you are finished.

As it stands now, the server will provide both unencrypted HTTP and encrypted HTTPS traffic. For better security, it is recommended in most cases to redirect HTTP to HTTPS automatically. If you do not want or need this functionality, you can safely skip this section.

To adjust the unencrypted Virtual Host file to redirect all traffic to be SSL encrypted, open the /etc/apache2/sites-available/000-default.conf file:

sudo nano /etc/apache2/sites-available/000-default.conf

Inside, within the VirtualHost configuration blocks, add a Redirect directive, pointing all traffic to the SSL version of the site:

/etc/apache2/sites-available/000-default.conf

<VirtualHost *:80>
        . . .
 
        Redirect "/" "https://your_domain_or_IP/"
 
        . . .
</VirtualHost>

Save and close the file when you are finished.

That’s all of the configuration changes you need to make to Apache. Next, we will discuss how to update firewall rules with ufw to allow encrypted HTTPS traffic to your server.

Je n’ai pas réalisé cette étape.

Now that we’ve made our changes and adjusted our firewall, we can enable the SSL and headers modules in Apache, enable our SSL-ready Virtual Host, and then restart Apache to put these changes into effect.

Enable mod_ssl, the Apache SSL module, and mod_headers, which is needed by some of the settings in our SSL snippet, with the a2enmod command:

sudo a2enmod ssl
sudo a2enmod headers
sudo a2ensite default-ssl
sudo a2enconf ssl-params

At this point, the site and the necessary modules are enabled. We should check to make sure that there are no syntax errors in our files. Do this by typing:

sudo apache2ctl configtest

If everything is successful, you will get a result that looks like this:

Output
Syntax OK

As long as your output has Syntax OK in it, then your configuration file has no syntax errors and you can safely restart Apache to implement the changes:

sudo systemctl restart apache2

With that, your self-signed SSL certificate is all set. You can now test that your server is correctly encrypting its traffic.

You’re now ready to test your SSL server.

Open your web browser and type

https://

followed by your server’s domain name or IP into the address bar:

https://server_domain_or_IP

Because the certificate you created isn’t signed by one of your browser’s trusted certificate authorities, you will likely see a scary looking warning like the one below:Apache self-signed cert warningThis is expected and normal. We are only interested in the encryption aspect of our certificate, not the third party validation of our host’s authenticity. Click ADVANCED and then the link provided to proceed to your host anyways:Apache self-signed override

You should be taken to your site. If you look in the browser address bar, you will see a lock with an « x » over it or another similar “not secure” notice. In this case, this just means that the certificate cannot be validated. It is still encrypting your connection.

If you configured Apache to redirect HTTP to HTTPS, you can also check whether the redirect functions correctly:

http://server_domain_or_IP

If this results in the same icon, this means that your redirect worked correctly. However, the redirect you created earlier is only a temporary redirect. If you’d like to make the redirection to HTTPS permanent, continue on to the final step.

If your redirect worked correctly and you are sure you want to allow only encrypted traffic, you should modify the unencrypted Apache Virtual Host again to make the redirect permanent.

Open your server block configuration file again:

sudo nano /etc/apache2/sites-available/000-default.conf

Find the Redirect line we added earlier. Add permanent to that line, which changes the redirect from a 302 temporary redirect to a 301 permanent redirect:

/etc/apache2/sites-available/000-default.conf

<VirtualHost *:80>
        . . .
 
        Redirect permanent "/" "https://your_domain_or_IP/"
 
        . . .
</VirtualHost>

Save and close the file.

Check your configuration for syntax errors:

sudo apache2ctl configtest

If this command doesn’t report any syntax errors, restart Apache:

sudo systemctl restart apache2

This will make the redirect permanent, and your site will only serve traffic over HTTPS.