In this post I will say something about FreeRadius config files, database connection, basic instruction how to insert user in database, etc. Before you step inside this post, I recommend reading part 1 and part 2.

I suppose you’re using RH based distros (Red Hat, CentOS, Fedora,..) and you already installed FreeRadius from source (config files are located in /usr/local/etc/raddb/). Now lets get back to FreeRadius source dir (the place where you extracted the tar.gz).

Inside redhat dir you can find freeradius-radiusd-init script which can be used for easy start/stop radiusd process. Copy this script to /etc/init.d/ dir

# cp freeradius-radiusd-init /etc/init.d/radiusd

Now open /etc/init.d/radiusd script and change the next lines

exec=${exec:=/usr/sbin/$prog}
config_dir=${config_dir:=/etc/raddb}
config=${config:=$config_dir/radiusd.conf}
pidfile=${pidfile:=/var/run/$prog/$prog.pid}
lockfile=${lockfile:=/var/lock/subsys/radiusd}

into

exec=${exec:=/usr/local/sbin/$prog}
config_dir=${config_dir:=/usr/local/etc/raddb}
config=${config:=$config_dir/radiusd.conf}
pidfile=${pidfile:=/usr/local/var/run/$prog/$prog.pid}
lockfile=${lockfile:=/var/lock/subsys/radiusd}

Save changes and exit from editor. (Notice above that we actually changed the path from / to /usr/local/)

Now you can easily start/stop radiusd process.

[root@ms /]# service radiusd
Usage: /etc/init.d/radiusd {start|stop|status|restart|condrestart|try-restart|reload|force-reload}

Also, you can exec chkconfig –level 235 radiusd on to start radiusd on boot.

Now lets get back to our setup.

I suppose you have at least one NAS (A Network Access Server (NAS) is a system that provides access to a network. In some cases also known as a Terminal Server or Remote Access Server (RAS).) NAS is a CLIENT for your radiusd server so please do not mess users and clients. Freeradius doesn’t interact with your users directly so “radius client” is another term for NAS.

The first step is to add your NAS to client list and to create a unique password. Inside clients.conf (/usr/local/etc/raddb/clients.conf) you can find the next lines

#client 192.168.0.0/24 {
#       secret          = testing123-1
#       shortname       = private-network-1
#}

Uncomment those lines and set up client IP address according to your addresses. In the example shown above, all IPs from 192.168.0.0/24 network will be able to use your radiusd server.

You can allow any IP with

client 0.0.0.0/0 {
       secret          = mysecret
       shortname       = myNAS
}

which means all IPs in the world can use my radius server (which is not recommended)…

To allow only one IP (in this case 192.168.0.15),

client 192.168.0.15 {
       secret          = mysecret
       shortname       = myNAS
}

Delete user Cleartext-Password := “password” line from users because we don’t need this any more.

Stop radiusd and start in debugging mode (radiusd -X).

You should see the similar lines

...............
radiusd: #### Loading Clients ####
 client localhost {
        ipaddr = 127.0.0.1
        require_message_authenticator = no
        secret = "testing123"
        nastype = "other"
 }
 client 192.168.0.15 {
        require_message_authenticator = no
        secret = "mysecret"
        shortname = "myNAS"
 }
...........

This means that radiusd will allow NAS with IP address 192.168.0.15 and secret mysecret. Ctrl+C to stop radiusd.

In case you want to use MySQL with freeradius, you should do the next steps. Before anything, you need to create a database for freeradius.

Connect as root to your mysql and exec next queries.

CREATE USER 'radius'@'localhost' IDENTIFIED BY  'radpass';
GRANT USAGE ON * . * TO  'radius'@'localhost' IDENTIFIED BY  'radpass';
CREATE DATABASE IF NOT EXISTS  `radius` ;
GRANT ALL PRIVILEGES ON  `radius` . * TO  'radius'@'localhost';

Another option is to use admin.sql script from raddb/sql/mysql dir.

CREATE USER 'radius'@'localhost';
SET PASSWORD FOR 'radius'@'localhost' = PASSWORD('radpass');
GRANT SELECT ON radius.* TO 'radius'@'localhost';
GRANT ALL ON radius.radacct TO 'radius'@'localhost';
GRANT ALL ON radius.radpostauth TO 'radius'@'localhost';

This script will set a little bit safer permissions where radius will be able only to write radacct and radpostauth tables. (Do not forget to change default username/pass shown above).

The next step is to import default Freeradius tables (the sql files can be found inside raddb/sql/mysql dir). You should import nas.sql and schema.sql. The nas.sql will create a table for your NASes. It is much easier to maintain the NAS list inside database then inside clients.conf. Also, you can add more fields to nas table so you can do other operations with your NAS.

After this operations you should have something like:

[root@ms mysql]# mysql -u radius -p
Enter password:
Welcome TO the MySQL monitor.  Commands END WITH ; OR \g.
Your MySQL connection id IS 23387
Server version: 5.0.77-log SOURCE distribution
 
TYPE 'help;' OR '\h' FOR help. TYPE '\c' TO clear the buffer.
 
mysql> USE radius;
Reading TABLE information FOR completion OF TABLE AND COLUMN names
You can turn off this feature TO GET a quicker startup WITH -A
 
DATABASE changed
mysql> SHOW TABLES;
+------------------+
| Tables_in_radius |
+------------------+
| nas              |
| radacct          |
| radcheck         |
| radgroupcheck    |
| radgroupreply    |
| radpostauth      |
| radreply         |
| radusergroup     |
+------------------+
8 ROWS IN SET (0.00 sec)
 
mysql>

Now we have a working database and we need to configure FreeRadius to use SQL.

radiusd.conf

Open radiusd.conf file (/usr/local/etc/raddb/radiusd.conf), and uncomment $INCLUDE sql.conf line inside modules section. Save changes and exit.

sql.conf

Open sql.conf and edit next lines

        # Connection info:
        server = "localhost"
        #port = 3306
        login = "radius"
        password = "radpass"
 
        # Database table configuration for everything except Oracle
        radius_db = "radius"

to fit your settings (database name, username and password).

dialup.conf

Then open /usr/local/etc/raddb/sql/mysql/dialup.conf and find the next lines (near the end)

 # Uncomment simul_count_query to enable simultaneous use checking
        simul_count_query = "SELECT COUNT(*) \
                             FROM ${acct_table1} \
                             WHERE username = '%{SQL-User-Name}' \
                             AND acctstoptime IS NULL"

Sometimes you will need to check users for simultaneous use and uncommenting sql in session section and uncommenting the query shown above will help you to do this.

default

Now open /usr/local/etc/raddb/sites-available/default and uncomment sql lines inside authorize, accounting and session sections. You can uncomment sql inside post-auth section too if you want to log login attempts (notice that this is not recommended for production servers. Your database can grow and eat up all free space in case someone tries to brute force your NAS.).

Then comment the next lines: files inside authorize section, detail, unix and radutmp inside accounting section and radutmp inside session section.

Please note that those lines we commented above are not important for now and commenting those lines can improve performance. Also, note that detail should remain uncommented in case you want to create ‘detail’ed log of the packets for accounting requests. You will need this in case you want to proxy accounting to another server.

Then save the file and check your config with radiusd -X (debugging mode).

After this you should see something like

rlm_sql (sql): Driver rlm_sql_mysql (module rlm_sql_mysql) loaded and linked
rlm_sql (sql): Attempting to connect to radius@localhost:/radius
rlm_sql (sql): starting 0
rlm_sql (sql): Attempting to connect rlm_sql_mysql #0
rlm_sql_mysql: Starting connect to MySQL server for #0
rlm_sql (sql): Connected new DB handle, #0
rlm_sql (sql): starting 1
rlm_sql (sql): Attempting to connect rlm_sql_mysql #1
rlm_sql_mysql: Starting connect to MySQL server for #1
rlm_sql (sql): Connected new DB handle, #1
rlm_sql (sql): starting 2
rlm_sql (sql): Attempting to connect rlm_sql_mysql #2
rlm_sql_mysql: Starting connect to MySQL server for #2
rlm_sql (sql): Connected new DB handle, #2
rlm_sql (sql): starting 3
rlm_sql (sql): Attempting to connect rlm_sql_mysql #3
rlm_sql_mysql: Starting connect to MySQL server for #3
rlm_sql (sql): Connected new DB handle, #3
rlm_sql (sql): starting 4
rlm_sql (sql): Attempting to connect rlm_sql_mysql #4
rlm_sql_mysql: Starting connect to MySQL server for #4
rlm_sql (sql): Connected new DB handle, #4

which means your freeradius server successfully connected to MySQL database.

There are hundreds of options inside the files shown above and it is impossible to explain all of them. Read comments inside config files and try to figure yourself about them. If you’re using another database scheme, you will need to set up sql.conf and dialup.conf according to your tables. All parameters are editable and it is very easy to understand them. For example if you have a large number on users (1000-xxxx) open sql.conf and increase num_sql_socks from 5 to 15 or 20.

You should not change/delete any other lines in the config file without reading and understanding the comments!

Populating tables and testing

This is the most important part. Before you continue, you need to know what actually do you want from FreeRadius. Which kind of connection do you expect, etc. Also, you need to know something about tables, attributes, operators, etc.

This is it for now…. Next time we will add some users inside database and see what we can do.

Stay tuned…