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LAMP Installation and Web hardening
LAMP is one of the most common web systems we find today. Letters L A M P stands for Linux , Apache, MySQL & PHP.
From your yesterday’s work, we already have our first objective ‘L’, i.e. Linux or in our case its Ubuntu. Therefore, let’s see how to install other three and then in to some security hardening.
Prerequisites
Before we begin, we need to have a non-root user account with sudo privileges set up on your Ubuntu 16.04 LTS server clean installation.
Check whether you can ping your vm from the pc using its domain name www.'yourdomain'.ws.learn.ac.lk
Installation of Apache
Apache is a web server application that is widely used in the internet for more than 20 years and it is a well-documented piece of Free and Open Source Software managed by Apache Foundation. (https://httpd.apache.org/)
Before installing we need to update our repositories. Therefore we will first add debian apache repo to our list and do a update on the list. Since we will be using sudo commands, It will ask you for your user's password as these processors will be granted root privileges.
sudo add-apt-repository ppa:ondrej/apache2
When Asked press ‘Enter’ to Continue. Once the ppa is imported do an update.
sudo apt-get update
Once the repo lists are updated run,
sudo apt-get install apache2
When asked press Y and hit Enter to continue, and the installation will proceed.
Check installed apache version details by issuing,
$ apache2 -v
NOTE: if you had installed apache2 while installing Ubuntu OS then we should update it to the latest by,
sudo apt-get --only-upgrade install apache2 -y
Now goto your browser and type http://www.'your domain'.ws.learn.ac.lk and check whether you are able to access the apache test page.
MySQL Installation
Once the web server is installed and running we need to install a database management system to host our dynamic data. For that we use MySQL database as another popular FOSS.
So to install MYSQL run,
sudo apt-get install mysql-server
Again you will be asked to press Y to continue. During the installation process you will be asked to type in and confirm a root password for your MySQL system. Please keep in mind that MySQL root is also similar to root access of your server and therefore choose a strong and unique password, never leave it blank.
As the installation completes let’s tighten some security in MySQL by running,
sudo mysql_secure_installation
Enter your MySQL root password when asked. As the first step it will ask
VALIDATE PASSWORD PLUGIN
where this will make your passwords associated with databases much stronger by enforcing password restrictions. Once you click y it will give three options LOW, MEDIUM, STRONG. Then select a level of password validation. Make sure to keep in mind that if you enter 1, for the medium level, you will receive errors when attempting to set any password which does not contain numbers, upper and lowercase letters, and special characters.
Then there will be several questions asked, please enter Y for every answer and enter.
Once the script ends running we can test our MySQL instance by login in to it.
mysql –u root –p
Enter your MySQL root password when requested.
Install PHP 7
As the last option of LAMP lets install PHP version 7.
type in,
sudo apt-get -y install php7.0 libapache2-mod-php7.0
the switch –y will automatically put yes on the installation process when it is prompted.
Once the installation is finished restart apache.
sudo service apache2 restart
To check php, lets create a test php file.
sudo nano /var/www/html/info.php
Note: /var/www/html/ is the default document root for apache in Ubuntu unless you have changed it in apache configuration.
Enter the following in info.php
<?php phpinfo(); ?>
Now let us call that file in a browser (e.g. http://www.'yourdomain'.ws.learn.ac.lk /info.php)
If your PHP 7 is working you will see all your php server settings in a one single place.
Enabling Virtual Hosts
Before we go further test your domain names are correctly resolving to the same server IP address by issuing Ubuntu dig commands.
dig @192.248.1.161 web1.’yourdomain’.ws.learn.ac.lk dig @192.248.1.161 web2.’yourdomain’.ws.learn.ac.lk
Next, create two directories on /var/www/ to host two separate web sites.
sudo mkdir /var/www/web1 sudo mkdir /var/www/web2
Create index pages on each directories containing following.
sudo nano /var/www/web1/index.php
You may change the content as appropriate.
<html> <head> <title>Web 1</title> </head> <body> <h1> <?php Echo "Hello, I’m Web1"; ?> </h1> </body> </html>
Default host configuration is located in /etc/apache2/sites-available/000-default.conf which serves any requests coming to its domain name or IP address. To make other two domains work, lets create virtual host files for each domain names;
sudo nano /etc/apache2/sites-available/web1.conf
with the following content,
<VirtualHost *:80>
ServerAdmin admin@yourdomain.ws.learn.ac.lk
ServerName yourdomain.ws.learn.ac.lk
ServerAlias web1.yourdomain.ws.learn.ac.lk
DocumentRoot /var/www/web1
ErrorLog ${APACHE_LOG_DIR}/error.log
CustomLog ${APACHE_LOG_DIR}/access.log combined
</VirtualHost>
Then create the virtual host for web2 as web2.conf on the same directory as web1.conf with the folowing.
<VirtualHost *:80>
ServerAdmin admin@yourdomain.ws.learn.ac.lk
ServerName yourdomain.ws.learn.ac.lk
ServerAlias web2.yourdomain.ws.learn.ac.lk
DocumentRoot /var/www/web2
ErrorLog ${APACHE_LOG_DIR}/error.log
CustomLog ${APACHE_LOG_DIR}/access.log combined
</VirtualHost>
Once both files are written these needs to be enabled by,
sudo a2ensite web1.conf sudo a2ensite web2.conf
Now restart the apache and check your browsers for following and see how three websites are hosted in one server.
http://www.yourdomain.ws.learn.ac.lk
http://web1.yourdomain.ws.learn.ac.lk
http://web2.yourdomain.ws.learn.ac.lk
CGI Scripts
CGI stands for Common Gateway Interface are useful for creating dynamic content on web page by transferring data from server to client. These scripts can be written in many languages such as bash, c, java, perl, python etc.
First we need to create a script firstbash.cgi in following location /usr/local/cgi-bin/ , you may need to
create it as sudo.
#!/bin/bash echo "Content-type: text/html" echo "" echo "My first CGI script"
Give the script file execute permissions
sudo chmod 705 /usr/local/cgi-bin/firstbash.cgi
Now to add this CGI on our web2 virtual host, edit /etc/apache2/sites-available/web2.conf as follows.
<VirtualHost *:80>
ServerAdmin admin@yourdomain.ws.learn.ac.lk
ServerName yourdomain.ws.learn.ac.lk
ServerAlias web2.yourdomain.ws.learn.ac.lkDocumentRoot /var/www/web2
<Directory /var/www/web2>
Require all granted
</Directory>
ScriptAlias /cgi-bin/ "/usr/local/cgi-bin/"
<Directory "/usr/local/cgi-bin/">
Options +ExecCGI
AddHandler cgi-script .cgi
Require all granted
</Directory>
ErrorLog ${APACHE_LOG_DIR}/error.log
CustomLog ${APACHE_LOG_DIR}/access.log combined
</VirtualHost>
After editing web2.conf lets enable CGI apache module and restart the server.
sudo a2enmod cgi sudo systemctl reload apache2
Visit following link and check-out your script.
http://web2.yourdomain.ws.learn.ac.lk/cgi-bin/firstbash.cgi
Apache Hardening
- Hide Apache version details:
By default, Apache displays the version of Apache web server installed with the name of the operating system. To hide this information, you need to edit /etc/apache2/conf-enabled/security.conf
sudo nano /etc/apache2/conf-enabled/security.conf
Add/edit the following line:
ServerSignature Off ServerTokens Prod
- Stop Directory Browsing
Rename index.html in /var/www/html as index2.html and try to access web server from outside. You will see the directory Listing as now we don’t have an Index. But better stop displaying directory listing. Therefore, edit /etc/apache2/apache.conf and remove Indexes key word from any Directory listing such as,
<Directory /var/www/> # Options Indexes FollowSymLinks Options -FollowSymLinks AllowOverride None Require all granted </Directory>
and restart apache. Now go back to your default web portal and check the results.
file/folder permissions
When you create or modify documents under /var/www/ as sudo those files and directories will belong to root user and root group. Apache is usually run by a user www-data and www-data group in Ubuntu. Therefore, if any document belongs to root will also be published as root has higher precedence than www-data. But if some malicious content are hosted, they can also be run under root opening lot of vulnerabilities to the public.
To secure publically accessible areas we can change user permissions by,
sudo chown -R www-data:www-data /var/www
Also if we had directories that are open for users to upload content we can restrict access by modifying access modes.
sudo chmod 664 /var/www/uploads
That will change file permissions to rw-rw-r—
Password protected Directory
When securing a directory it is a common practice we use a password to enter that path. Also in apache2 we can specify a password by creating an apache user and using .htaccess as needed.
First install Apache Utiities;
sudo apt-get install apache2-utils
On your virtual host configuration file add or modify following inside the <Document> ... </Document>.
AllowOverride AuthConfig
Next create an authenticate user.
sudo htpasswd -c /etc/apache2/.htpasswd yourname
This will ask you to enter a new password and conform it for the new user. If you want to add another user, try with the same command above with new username. You can view the contents of the .htpassword file by
sudo cat /etc/apache2/.htpasswd
next we need to grant permission to www-data user.
sudo chown www-data:www-data /etc/httpd/.htpasswd sudo chmod 0660 /etc/httpd/.htpasswd
After that create a directory called “mystuff” inside the directory web1, create an html page of your choice inside the directory as sudo and change ownership to www-data.
sudo mkdir /var/www/web1/mystuff sudo nano /var/www/web1/mystuff/index.html sudo chown –R www-data:www-data /var/www/web1/mystuff/*
Now create .htaccess file inside mystuff directory
sudo nano /var/www/web1/mystuff/.htaccess
Add following content
AuthType Basic AuthName "Restricted Content" AuthUserFile /etc/apache2/.htpasswd Require valid-user
Now restart apache and browse to the newly created directory from your browser and check what is changed.
HTTPS configuration using Let’s Encrypt
Install letsencrypt client on the server
sudo apt-get install python-letsencrypt-apache
Run the following to enable https for the selected domain specified with –d.
sudo letsencrypt --apache -d www.yourdomain.ws.learn.ac.lk
During the process you will be requested to enter a valid e-mail address where it will be used to send you details of your certificate and alerts like certificate expiry. Also you will be able to pick between enabling both http and https access or forcing all requests to redirect to https. It is usually safest to require https, except you have a specific necessity for unencrypted http traffic.
If you want to enable https for other domains, then run the above with the other domain names as well.
NOTE: If your put several domains in single command with multiple –d flags then all those sites will be issued single ssl certificate with multiple domain names. This is useful if you want to certify a specific server name and a parent domain both at the same time. (Eg. www.learn.ac.lk , learn.ac.lk both will end up in same landing page without generating errors.) Once letsencrypt finishes, go to https://www.ssllabs.com/ssltest/analyze.html?d=www.yourdomain.ws.learn.ac.lk&latest
and check https connectivity.
Auto Renewal of Certificates:
Let’s Encrypt certificates are normally valid for 90 days only. Therefore, we have to renew these certificates at least once every 3 months. This can be done automatically by creating a cron job in Linux to execute letsencript renew command. To edit cron Jobs
sudo crontab –e
then it will ask for an editor. To use nano the default editor press enter.
At the bottom of the page insert below and save/exit,
30 4 25 */2 * /usr/bin/letsencrypt renew >> /var/log/le-renew.log
Above command will execute “/usr/bin/letsencrypt renew” on 25 th day in every two months and will write the output to a file called “/var/log/le-renew.log” Also as a best practice it is better to disable port 80 or plain HTTP traffic to your server. But if your directly disable Port 80 and allow only 443 then we have to manually type “https://” before your exact url in browsers. Therefore, better to redirect all HTTP traffic to port443 from your server configuration without disabling. So to do that we need to put a redirect in each virtual host conf. files.
Edit port 80 virtual host configuration files and add these in bottom just before the line </VirtualHost>
RewriteEngine on
RewriteCond %{SERVER_NAME} = www.yourdomain.ws.learn.ac.lk
RewriteRule ^ https://%{SERVER_NAME}%{REQUEST_URI} [END,QSA,R=permanent]
</VirtualHost>
Then enable mod-rewrite in apache and restart..
sudo a2enmod rewrite sudo systemctl reload apache2
Now test your configuration by browsing to http://www.yourdomain.ws.learn.ac.lk and see how it redirects
http2
HTTP/2 support is included in Apache 2.4.17 and upwards. Enable HTTP/2 module by executing,
sudo a2enmod http2
then add below to each individual ssl virtual host files to enable respectively.
Protocols h2 http/1.1
To enable http/2 globally you can add following to the apache.conf
Protocols h2 h2c http/1.1
Once those lines are added restart apache and visit https://tools.keycdn.com/http2-test to check http2 configuration.
