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'''Weight:''' 5% of the overall grade
'''Due Date: Week 13 - week of December 6 ('''Check with Week 13 <br />Refer to your Professor instructor for exact date''').submission instructions
{{Admon/important | Very ImportantIt is YOUR responsibility to Backup your centos3 VM for this Assignment! | Before making any changes You are required to frequently backup your system configuration, backup VM prior to exiting a work session during this assignment. Your instructor will NOT accept the original fact that your hard disk crashed and lost all of your work. If you properly backed up your VM images and xml configuration files into the <code>/backups</code> directoryto a USB, then you can purchase a new hard-disk or wipe and recreate your hard disk and restore your VMs.}}<br>
== Introduction and Purpose ==
In this assignment, you will demonstrate the skills you have learned to this point by configuring two services: a '''database server ''' and a '''web server'''. You will install and use a database-backed web application, MediaWiki'''Wordpress''', to show that these services have been installed properly. Finally, you You will also configure the SELinux security system and the web server to serve files in the <code>public_html</code> subdirectory of each user's home directory, including a short web script. In this assignment, you will attempt to maintain a high level of security, by using SELinux and the iptables firewall to guard against unauthorized access. This lab may be performed using any combination of your virtual machines and/or host disk pack. == About SELinux == SELinux stands for ''Security Enhanced Linux'' and is based on research performed at NSA and other locations. Where the normal Unix/Linux security system, based upon file permissions, is a ''discretionary access control'' system (DAC), SELinux is a ''mandatory access control'' system (MAC). This means that it attempts to enforce a consistent policy across the entire system, regardless of settings that any user has configured. SELinux decisions are based on the ''security context'' of system resources such as files and processes. The security context consists of a user, role, type, and sensitivity component; you can see the security context of files and processes by adding the <code>-Z</code> option to further enhance the <code>ls</code> and <code>ps</code> commands: $ ls -lZ drwxr-xr-x. root root '''system_u:object_r:file_t:s0''' arm drwxr-xr-x. chris chris '''unconfined_u:object_r:user_home_t:s0''' arm2 drwxrwxr-x. chris chris '''unconfined_u:object_r:user_home_t:s0''' bin drwxr-xr-x. chris chris '''unconfined_u:object_r:user_home_t:s0''' Desktop drwxr-xr-x. chris chris '''unconfined_u:object_r:user_home_t:s0''' Documents drwxr-xr-x. chris chris '''unconfined_u:object_r:user_home_t:s0''' Downloads -rw-------. chris chris '''unconfined_u:object_r:user_home_t:s0''' fedora0.ks -rw-------. chris chris '''unconfined_u:object_r:user_home_t:s0''' fedora1.ks -rw-------. chris chris '''unconfined_u:object_r:user_home_t:s0''' fedora2.ks -rw-------. chris chris '''unconfined_u:object_r:user_home_t:s0''' fedora3.ks -rw-rw-r--. chris chris '''unconfined_u:object_r:user_home_t:s0''' foo -rw-r--r--. chris chris '''unconfined_u:object_r:user_home_t:s0''' hosts drwxr-xr-x. chris chris '''unconfined_u:object_r:user_home_t:s0''' Music drwxr-xr-x. chris chris '''unconfined_u:object_r:user_home_t:s0''' Pictures drwxrwxr-x. chris chris '''unconfined_u:object_r:user_home_t:s0''' play drwxr-xr-x. chris chris '''unconfined_u:object_r:user_home_t:s0''' Public drwxr-xr-x. chris chris '''unconfined_u:object_r:user_home_t:s0''' Templates drwxr-xr-x. chris chris '''unconfined_u:object_r:user_home_t:s0''' Videos -rw-r--r--. chris chris '''unconfined_u:object_r:user_home_t:s0''' x [chris@muskoka ~]$ ps -Z LABEL PID TTY TIME CMD '''unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023''' 2595 pts/1 00:00:00 bash '''unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023''' 2612 pts/1 00:00:00 ps The SELinux policy controls the interactions between security contexts. For example, the policy may specify that the Apache httpd webserver cannot read files in <code>/etc</code>, so if an attacker finds a way to make httpd (or a script run by httpd) read a file in <code>/etc</code>, SELinux will recognize that this is not normal and will deny the access. Since this is done at the kernel level, httpd will get a "file not found" error, even though the file is present, and there is no way for httpd to work around that error. === SELinux Context Commands === There are two main commands used to set the SELinux security context of files:# chcon - sets the security context of a file to a particular value#* Example: setting the ''type'' of a file: <code>chcon -t ''unconfined_t'' ''/tmp/foo''</code>#* Example: setting the user/role/type of a file: <code>chcon ''unconfined_u:object_r:user_home_t'' ''~/foo''</code># restorecon - resets the default security context of a file#* Example: reset the context of one file: <code>restorecon /etc/services</code>#* Example: recursively reset the contexts of all of the files in a directory: <code>restorecon -R ~</code> You can reset the default security context of the entire your computer system at the next boot with this command: touch /.autorelabel === SELinux Booleans === SELinux policy can be tuned (without writing an entirely new policy) through the use of ''booleans'' or option switches. Each boolean can have a value of on (1) or off (0). The <code>getsebool</code> and <code>setsebool</code> commands can be used to view and set SELinux boolean values: {|class="mediawiki sortable" border="1" cellspacing="0"!Command!Description|-|<code>getsebool -a</code>|Displays all SELinux booleans|-|<code>getsebool ''foo''</code>|Displays the SELinux boolean ''foo''|-|<code>setsebool ''foo'' ''value''</code>|Sets the SELinux boolean ''foo'' to ''value'' (where ''value'' is 0 or "off", or 1 or "on")|} === SELinux Graphical Tools ===
== Installing Packages==
=== MySQL =Configuring Apache ==
# Start the MySQL httpd service (mysqld)using '''systemctl'''.# '''When started for Ensure that the first time, this httpd service will print a message telling starts automatically during boot.# Confirm that you how can connect to set your web server using a password and take other basic steps to secure the the MySQL server.web browser -- both from centos3 (you can test using '''links''' Follow those instructions to set a password, recording ) as well as from the host. You should see the detail of what you do for later useApache Test Page.# Configure this software If you can't connect to start when it from outside the system machine - perhaps your firewall is bootedblocking access to the web server.
=== MediaWiki =Configuring MySQL ==
# Edit MediaWikiStart the MySQL service (mysqld or mariadb) using '''systemctl'''s httpd configuration file, <code>/etc/httpd/conf.d/mediawiki.conf</code>#* Uncomment Ensure that the first two <code>Alias<mysqld/code> linesmariadb service starts automatically during boot.#* Reload the httpd configuration using You may get messages after starting the <code>MySQL service</code> command# Access <code>http://localhost/wiki</code> on for the machine on which the web server is running (this will first time. Do not work if done remotelyignore these messages, unless it will tell you use an ssh tunnel so that the access appears how to set a password and take other basic steps to be coming from the local host). You will see secure the MediaWiki welcome page; click on the setup linkMySQL server.# Enter Follow those instructions to set a password, recording the setup information detail of what you do for your wiki:later use.#* Enter a name for If you do not see any messages, research how you can secure the wiki#* Enter your learn e-mail address as MySQL installation and set the contact information#* Disable all eMySQL-mail featuresroot password.#* Leave the database host as Read those messages carefully, you are setting up a production MySQL server and there shouldn't be any "localhosttest"databases or anonymous users or users without a password.#* Set up a database your MySQL root passwordto your learn ID (without the @senecac.on.ca part).#* Get MediaWiki This following part is challenging so take your time and read the instructions to make sure you do it properly, we have to set up the superuser account a dedicated user and database for wordpress:## Start by checking the appropriate box and entering the superuser password ('''Notelooking at http:''' This is the database superuser password, NOT the root password)//codex.wordpress.org/Installing_WordPress# Click Using_the_MySQL_Client where you will find instructions for the "Install MediaWiki!" buttonsetup.# Once the setup is complete, you # You will need to move run those commands in a file within the MediaWiki directory (inside <code>/var/www</code>). Refer to the directions in the confirmation web pagecentos3 terminal.## Your adminusername is root## Your databasename is myblog## Your wordpressusername is your learn ID## The password should also be your learn ID## Your hostname is localhost
# Configure httpd to serve Download the <code>~/public_html</code> directories of latest .tar.gz version from wodpress.org into your userscentos3 (use wget). This will require changes to <code># Extract it into '''/etcvar/httpdwww/conf/httpd.conf</code> as well as html'''# Now we need to allow Apache to modify the SELinux configurationwordpress installation. See To do this use chown -R to make the man page for <code>httpd_selinux</code> owner and group of every file and the Apache [http://httpd.directory inside wordpress "apache.org/docs/2.2/ httpd documentation] for details".# Prove that this works Check your work so far by creating a page in pointing your <code>~/public_html</code> directory. The URL will be <code>web browser to http://''hostname''centos3/wordpress/~where you will get an error starting with "There doesn''yourt seem to be a wp-user-id''/</code>config.php file"# Create a short web script which displays Copy the available disk space on the computerwp-config-sample.php file to wp-config. At its most basic level, a web script is php and edit the same as a regular script, with this additional requirementnew file:#* It must output Change the line "Content-type: text/plain" or "Content-type: text/html" (depending on whether DB_NAME, DB_USER, DB_PASSWORD to the script output is plain text or HTML), followed by a blank lineappropriate values.# Name the script <code>~/public_html/diskfree.cgi</code> - The URL will be <code>Now go back to http://''hostname''centos3/wordpress/~''your-user-id''you should see a Wordpress Welcome/diskfreeSetup page.cgi</code># Configure httpd and SELinux to allow your script * Set the title to Your Name's Blog. For example for me it would be run from "Andrew Smith's Blog"#* Set the web. This will require changes password to <code>/etc/httpd/conf/httpdyour learn ID.conf</code> as well as #* Set the SELinux configuration (possibly including both booleans and SELinux context)email to your Seneca email address. As with step 1#* Click "Install Wordpress", you should see the man page for <code>httpd_selinux</code> and the Apache [http://httpd.apache.org/docs/2.2/ httpd documentation] for details. {{Admon/tip|Hint|Look for an a "add-handlerSuccess!" line in your httpd.conf filemessage.}}
== Write-up ==
== Submitting the Your Assignment ==
'''Due date:''' Your professor name will require be called in the lab on the due date for the assignment. If you to submit this assignment are not there when your name is called - you will lose 20% of your mark. In that case you may show me your submission in at least one the second lab that week instead. Assignments submitted after that will receive a grade of two ways:0, but must still be completed satisfactorily in order to pass the course.
{| class="wikitable" border== Section C "1"! Task !! Maximum mark !! Actual mark|-| Correct packages installed || 1 |||-| Firewall setup properly || 2 |||-| Apache set up and running || 2 |||-| MySQL set up correctly || 3 |||-| Wordpress extracted correctly || 1 |||-| Wordpress set up correctly || 2 |||-| Wordpress showing in Firefox || 1 |||-| Everything ready to show || 2 |||-| First blog post || 3 |||-| Second blog post || 3 |||- Brian Gray ===| '''Total''' || 20 ||