Managing HotSpot Clients With FreeRadiusDashamir Hoxha <dashohoxha@gmail.com> Copyright (C) 2008 Dashamir Hoxha. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.1 or any later version published by the Free Software Foundation; with no Invariant Sections, with no Front-Cover Texts, and with no Back-Cover Texts. A copy of the license is included in the section entitled "GNU Free Documentation License."

Abstract: This paper describes how to set up a HotSpot service, using FreeRadius for AAA. Client accounts in radius are managed with HotSpot Manager. MikroTik, ChilliSpot, CoovaChilli and CoovaAP can be used as hotspot servers (access points).

1. HotSpot Manager

1.1. Introduction

HotSpot Manager is a web application that can be used to manage the users of a network of HotSpot access points. The HotSpot access points are LinkSys WRT54GL wireless routers, with CoovaAP firmware (which provides HotSpot service via coova-chilli). The authentication of the internet users (clients) is done in a radius server (freeRadius).

The application supports more than one domain (network). Each domain can have one or more NASes (access points / wireless routers / HotSpot nodes). The number of access points for each domain is not limited. Each domain can have one or more managers that are created by the administrator (superuser) of the application. The manager of a domain can create, modify and delete the internet users of the domain. The internet user of a domain can get hotspot access to internet through each of the domain access points (NASes), but cannot login through the access points of the other domains. The domain manager assigns a certain internet service to the user, which defines the bandwidth of the user, the expiration time of the service, etc. The services are created and defined by the application administrator, which also makes available some of the services to each domain.

Grouping and managing access points and internet users into domains can be useful for hierarchical management of the network. For example an organization (or office, or business) can manage itself the connection to internet of its own staff. The application also allows to limit the number of access points and clients of each domain. Also each domain can have its own customized login page.

1.2. Features

Features that are currently implemented:

Support for multiple domains.

Each domain can have any number of NASes.

Each domain can have its own customized login page.

Support for several services.

An admin can have one or more domains and one domain can have one or more admins.

Actions of the users can be audited easily.

Optional integration with Radius Manager.

Features that may be implemented in the future:

More flexible types of services (including traffic limits, online time, etc.)

Automatic check for the limits of the clients and automatic interruption of the service in case that the limits are reached.

Automatic notification to the clients and admins when the internet usage approaches the limits.

Usage statistics about clients, domains etc.

Clients should be able to see their status and statistics.

Google map with the locations of the NASes (HotSpot-s).

Online registration of the clients and the possibility to pay by credit card, paypal etc.

Authentication of the users/clients by digital certificates (instead of username/password).

Scratch card generation?

Payment recording and billing functions?

1.3. Radius Manager

The application is also integrated with Radius Manager, which is an application for managing the database of freeRadius, services, clients, etc. (it has even some simple billing functionality). Unfortunately, Radius Manager is not free software (open source). So, the integration with Radius Manager is optional and HotSpot Manager can also work standalone (it does not depend on it).

The benefits of integrating with Radius Manager are these:

For each client (internet user) you can see in Radius Manager some usage statistics: is it online or not, history of connection/disconnection times, the download/upload traffic that it has done each time, etc.

Radius Manager has some cron jobs that check periodically expiration times of the clients, approaching download/upload limits etc. It can also send notification emails to the clients, disconnect them automatically, etc.

The same radius can be used for other services as well, e.g. PPPoE, using MikroTik as a NAS, etc.

The scratch card generator, billing functions etc. of Radius Manager can be useful as well.

However, HotSpot Manager may support some of these functions in the future releases...

1.4. Installation

Download it from http://sourceforge.net/projects/netaccess/files/hsmanager/0.5/hsmanager-0.5.tar.gz/download, and extract it:

bash$ tar xfz hsmanager-0.5.tar.gzbash$ mv hsmanager-0.5 hsmanager

Alternatively, get the code of the application from subversion at SourceForge:

bash$ cd /var/www/bash$ svn co https://netaccess.svn.sourceforge.net/svnroot/netaccess/\hotspot-manager/trunk hsmanagerbash$ cd hsmanager/bash$ svn co https://phpwebapp.svn.sourceforge.net/svnroot/phpwebapp/web_app/trunk \ web_app

Then, modify hsmanager.cfg accordingly and run sudo ./install.sh .

The parameters in hsmanager.cfg are these:

Connecting to the database of the application:

### parameters for connecting ### to the database of the applicationappdb_host=localhostappdb_name=hsmanagerappdb_adminuser=rootappdb_adminpass=appdb_user=hsmngappdb_pass=hsmngpassappdb_allowed_hosts='localhost'

The adminuser user should be able to create databases and users and to grant permissions to them. The user is the database user that is used by the application to access the database. The parameter allowed_hosts contains the host(s) where the application is installed (relative to the database host; for example it can be '192.168.100.%'.

Connecting to the database of radius:

### parameters for connecting ### to the database of radiusraddb_host=localhostraddb_name=radiusraddb_adminuser=rootraddb_adminpass=raddb_apiuser=hsmng1raddb_apipass=hsmngpassraddb_allowed_hosts='localhost'

The adminuser user should be able to create databases and users and to grant permissions to them. The user is the database user that is used by the application to access the database. The parameter

allowed_hosts contains the host(s) where the application is installed (relative to the database host; for example it can be '192.168.100.%'.

Note: The database where the data of the application are stored is different from the database of radius, this is why there are two different sets of configurations.

Important: If appdb_host is the same as raddb_host (both databases are located in the same server), then appdb_user and raddb_apiuser should be different. Otherwise there will problems, because the application uses persistent connections, and the php persistent connections are the same when both host and user (and password) are the same.

Parameters about radius:

### radius configurationrad_prefix=/usr/localintegrate_with_rm=true

The parameter rad_prefix can be empty, /usr/local , etc. The parameter integrate_with_rm can be true or false . If you have not already installed Radius Manager , then make if false .

### radius tables#nas=nas#radacct=radacct#radcheck=radcheck#radgroupcheck=radgroupcheck#radgroupreply=radgroupreply#radippool=radippool#radpostauth=radpostauth#radreply=radreply#radusergroup=usergroup

These are not functional yet.

Parameters about the HotSpot configuration of the NASes:

### hotspot configurationhs_config_dir=/usr/local/hotspot/confighs_radius_server1=192.168.25.11hs_radius_server2=192.168.25.11

The parameter hs_config_dir is the directory where the CoovaChilli configuration parameters are saved (for each domain).

1.5. Administration

First login as superuser. Superuser has access to all the modules of the application.

Then go to the module of Services and create some. Right now, only upload and download rates are saved in the radius database; the other features are not working yet.

Next, go the module of Domains and create some domains. Here, it is possible to select which services will be available to the clients of the domain (at least one service should be selected). The number of NASes and the number of clients of the domain can be limited as well (if they are zero, then there is no limitation).

Then, go to the module of Users and create some users of the application. These are the users that are permitted to access the application, not the internet users (the internet users are called clients). For each user set proper access rights: which modules and which domains he can access. A typical domain administrator has access only to one domain (his own domain), and to the modules: NASes, Clients and Logs. A user can administrate more than one domain (add them in separate lines), and one domain can have more than one admin. When a user logs into the application, his access rights will be restricted so that he can see and modify only the data that he is allowed to. For example, he will be able to see and modify only the NASes, clients and logs of his domains.

In order to register NASes and clients, now you can logout from the application (by closing all the windows of the browser) and then login as a normal user (domain administrator). Adding NASes and clients can also be done by the superuser, since he has access everywhere.

While adding NASes (HotSpot servers/routers) the important fields are the MAC and IP, which are used to allow the NAS to connect to radius and to identify to which domain it belongs. The other fields (Gateway, DNS etc.) are just informational (maybe later they can be used to configure the NAS automatically).

For the clients, the most important fields, besides Username and Password, are the Service and the Expiration Time. The other limits (Download Limit etc.) are not functional yet.

Then you can go to the module of Logs and see the activity that is done in the application by you and the other users. The logs can be filtered by time, event etc, so that you can find easily what you are looking for. The logs that are displayed are restricted by the domains to which the user has access.

The module Settings is meant for the users to update their own data and for the domain admins to see the data of their domains and to update some of them.

The module Misc right now has just one important submodule, which is used to backup/restore the

data of the database. In the future releases it may contain other things as well.

1.6. Diagrams

2. FreeRADIUS

2.1. Installing

I installed FreeRADIUS on Fedora. First I installed the packages freeradius and freeradius-mysql :

bash# yum install freeradius freeradius-mysql

Then I enabled the service radiusd and started it:

bash# /sbin/chkconfig --list radiusdbash# /sbin/chkconfig radiusd onbash# /sbin/chkconfig --list radiusd

bash# /sbin/service radiusd start

Since freeradius uses the ports 1812 and 1813 (see e.g. the file /etc/services ), I had to open these ports in the firewall, both for tcp and udp . In order to do this, I edited the file /etc/sysconfig/iptables and added there these lines:

-A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp --dport 1812 -j ACCEPT-A RH-Firewall-1-INPUT -m udp -p udp --dport 1812 -j ACCEPT-A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp --dport 1813 -j ACCEPT-A RH-Firewall-1-INPUT -m udp -p udp --dport 1813 -j ACCEPT

To apply these modifications in firewall, I restarted the service iptables:

bash# /sbin/service iptables restart

Tip: To check that the ports 1812 and 1813 are open in the firewall, we can use one of these commands:

bash# /sbin/service iptables status | grep 1812bash# /sbin/iptables-save | grep 1812

2.2. Testing

Just to test that FreeRADIUS is correctly installed and works, we can make a simple configuration using the standard text files, like this:

Edit the file /etc/raddb/clients.conf . At the section client 127.0.0.1 modify the value of secret , for example make it local1 . The entry client 127.0.0.1 { . . . } will allow the localhost to use the radius service.

Edit the file /etc/raddb/users . Uncomment there the test user steve (or create another user with similar details). It should look like this:

steve Cleartext-Password := "testing" Service-Type = Framed-User,

Framed-Protocol = PPP, Framed-IP-Address = 172.16.3.33, Framed-IP-Netmask = 255.255.255.0, Framed-Routing = Broadcast-Listen, Framed-Filter-Id = "std.ppp", Framed-MTU = 1500, Framed-Compression = Van-Jacobsen-TCP-IP

Edit /etc/raddb/radiusd.conf and make sure that authorization using files is enabled. (It should be enabled by default, so in general you don't need to modify anything.)

Now we can use the command radtest to request access for user steve with password testing :

bash# radtest --helpbash# radtest steve testing 127.0.0.1 10 local1bash# radtest steve testing localhost 10 local1bash# radtest steve testingX 127.0.0.1 10 local1bash# radtest steve testing 127.0.0.1 10 local1X

In the first and second tests you should get the answer 'Access-Accept'. In the last two tests you should get the answer 'Access-Reject'.

Tip: In order to get more details about what happens in the server, run radiusd in debug mode. First stop the service: /sbin/service radiusd stop , then run it like this: /usr/sbin/radiusd -x or /usr/sbin/radiusd -X .

Note: If you have Windows, you may also wish to use NTradPing (downloadable from MasterSoft ) instead of radtest. If you do this, or test from any other machine, remember to put your PC (or the other machine) in your NAS list in the file /etc/raddb/clients.conf .

2.3. Using MySQL

Now that radius is installed and we have tested that it works correctly, we can create a mysql database for it and configure radius to use this database.

First let's create a new database and a new database user:

bash$ mysql -p -u rootmysql> CREATE DATABASE radiusdb;mysql> GRANT ALL ON radiusdb.* TO raduser@localhost IDENTIFIED BY "radpass";mysql> exit;

Now lets create the tables of the database by running the SQL script file that is in the directory freeradius/doc/examples/:

bash$ mysql -p -u root -D radiusdb < /usr/share/doc/freeradius-1.1.7/examples/mysql.sql

We should modify now /etc/raddb/sql.conf by setting there the database, the username and the password that are needed to connect to the mysql server:

# Connect info server = "localhost" login = "raduser" password = "radpass"

# Database table configuration radius_db = "radiusdb"

Note: For testing/debug purposes, change sqltrace to yes. Then, freeradius will dump all SQL commands to the debug output.

Note: You may also need to modify the line about sql_user_name in this file.

Edit the file /etc/raddb/radiusd.conf and make there these modifications:

Uncomment the line saying 'sql' in the authorize{} section and comment the line saying 'files'.

Also uncomment the line saying 'sql' to the accounting{} section to tell FreeRADIUS to store accounting records in SQL as well. This file should then look something like this:

authorise { preprocess chap mschap suffix eap # files sql pap}

accounting { # We leave "detail" enabled to _additionally_ log accounting to /var/log/radius/radacct detail sql}

2.4. Testing MySQL

Enter some data in the database:

bash$ mysql -u raduser -p radpasswmysql> USE radiusdb;mysql> SHOW TABLES;mysql> INSERT INTO usergroup (UserName, GroupName) --> VALUES ("radiustest", "testgroup");mysql> SELECT * FROM usergroup;mysql> INSERT INTO radcheck (UserName, Attribute, Value) --> VALUES ("radiustest", "Password", "testpassword");mysql> SELECT * FROM radcheck;mysql> INSERT INTO radgroupreply (GroupName, Attribute, op, Value) --> VALUES ("testgroup","Framed-Compression","==","Van-Jacobsen-TCP-IP");mysql> INSERT INTO radgroupreply (GroupName, Attribute, op, Value) --> VALUES ("testgroup","Framed-Protocol","==","PPP");

mysql> INSERT INTO radgroupreply (GroupName, Attribute, op, Value) --> VALUES ("testgroup","Framed-MTU","==","1500");mysqk> INSERT INTO radgroupreply (GroupName, Attribute, op, Value) --> VALUES ("testgroup","Service-Type","==","Framed-User");mysql> quit;

Then stop the service /sbin/service radiusd stop and run radiusd in debug mode: /usr/sbin/radiusd -x or /usr/sbin/radiusd -X .

Now check access for the user radiustest with password testpassword :

bash# radtest radiustest testpassword localhost 10 local1Sending Access-Request of id 224 to 127.0.0.1 port 1812 User-Name = "radiustest" User-Password = "testpassword" NAS-IP-Address = 255.255.255.255 NAS-Port = 10rad_recv: Access-Accept packet from host 127.0.0.1:1812, id=224, length=44 Framed-Compression = Van-Jacobson-TCP-IP Framed-Protocol = PPP Framed-MTU = 1500 Service-Type = Framed-User

3. SQL API

This SQL API helps to access the database of the freeRadius (or Radius Manager) from the HotSpot Manager (which manages the services and users). it is a library of MySQL procedures, which can be used to access and modify the database. It encapsulates (hides) the complexity of the database from the outside programmer. The programmer doesn't have to know what tables or fields are there in the database, but just needs to know the procedures/functions that are available in the API, their parameters, return values, etc. It also makes simpler the code of the program, because instead of using complicated SQL queries, it just needs to call a procedure with the appropriate parameters.

3.1. Radius SQL API

procedure user_save(p_username varchar(64), p_password varchar(253), p_service varchar(64), p_domain varchar(253) )

Takes the parameters: username, password, service. In case that such a user exist, it is deleted first, and then new records about the user are inserted.

> call radius.user_save('user-1','passw-1','test-1','domain-1'); -- create the user 'user-1' which has access at 'domain-1' > call radius.user_save('user-1','xyz','test-1','domain-1'); -- change the password of 'user-1'

function user_check(p_username varchar(64)) returns varchar(64)

Used to check whether a user already exists in radiusdb (in the table radcheck). If there is such a user, then it returns its username.

> select radius.user_check('user-1') as username; +----------+ | username | +----------+ | user-1 | +----------+ > select radius.user_check('user-2') as username; +----------+ | username | +----------+ | | +----------+

procedure user_get(p_username varchar(64), p_service varchar(64) )

Returns the data of a given user. Parameters are username and service patterns. Matching is done with LIKE. The records that are returned have the fields: username, service

> call user_get('user-1', '%'); -- get the data of 'user-1' > call user_get('%', 'service-1'); -- get the data of all the users that have the service 'service-1' > call user_get('%', '%'); -- get the data of all the users

procedure user_del(p_username varchar(64))

Delete the given user.

> call radius.user_del('user-2'); -- delete user 'user-2'

procedure service_save(p_service_name varchar(64), p_download_rate int(11), p_upload_rate int(11))

Save (add or update) a service. Takes the parameters: service_name, download_rate, upload_rate. Download and upload rates are integers in Kbps. If a service with such a name already exists, it is deleted first.

> call radius.service_save('test-1', 256, 128); -- create the service test-1 with 256Kbps download and 128Kbps upload > call radius.service_save('test-2', 512, 128); -- add another service > call radius.service_save('test-2', 512, 256); -- change the upload rate of the service test-2

procedure service_get(p_service_name varchar(64))

Return a list of services that match the given parameter. Matching is done with LIKE. The result that is returned contains the fields: service, dwmload rate, upload rate, where the rates are integers of Kbps.

> call radius.service_get('test-1'); -- get the data of the service 'test-1' > call radius.service_get('%'); -- get the data of all the services +----------+---------------+-------------+ | service | download_rate | upload_rate | +----------+---------------+-------------+ | test-1 | 256 | 128 | | test-2 | 512 | 256 | +----------+---------------+-------------+

procedure service_del(p_service varchar(64))

Delete the service with the given name.

> call radius.service_del('test-2'); -- delete the service that is named 'test-2'

procedure change_service_name(p_old_service varchar(64) p_new_service varchar(64))

Changes the name of a service, so that all the clients that were using the old service now use the new service.

> call radius.change_service_name('test-2', 'test2'); -- change the name of the service 'test-2' to 'test2'

3.2. RM SQL API

procedure rm_user_save(p_username varchar(32), p_password varchar(32), p_service_id int(11), p_expiration_date date, p_fullname varchar(30), p_email varchar(50))

Save a user in the table rm_users of the Radius Manager. Takes these parameters:

username, password, service_id, expiration_date, fullname, email

In case that such a user exist, it is deleted first, and then new records about the user are inserted.

procedure rm_user_del(p_username varchar(32))

Delete the given user.

procedure rm_user_get(p_username varchar(32))

Returns the data of a given user. Gets the username of the user as a parameter (type: varchar(32)), and returns one or more records with the data of the users who match the data of the username. Matching is done with LIKE. It may return nothing if such a user does not exist. The record that is returned has these fields:

username, srvname, expiration, enabled

procedure rm_nas_insert(p_ip varchar(128), p_name varchar(128), p_secret varchar(60), p_description varchar(200))

Add a new record in the table 'nas'.

procedure rm_nas_update(p_ip varchar(128), p_name varchar(128), p_secret varchar(60), p_description varchar(200))

Update a record in the table 'nas'.

procedure rm_nas_delete(p_ip varchar(128))

Delete a record in the table 'nas'.

function rm_nas_check(p_ip varchar(128)) returns varchar(128)

Used to check whether an IP is already registered in the nas table. If it is registered, then it returns the IP, otherwise returns 'not-found'.

> select radius.rm_nas_check('192.168.0.10') as ip; +--------------+ | ip | +--------------+ | 192.168.0.10 | +--------------+ > select radius.rm_nas_check('192.168.0.11') as ip; +-----------+ | ip | +-----------+ | not-found | +-----------+

4. HotSpot Servers

There are different ways for implementing a HotSpot server. Here I am going to describe how to configure a HotSpot service in MikroTik, how to install and configure ChilliSpot and CoovaChilli on a linux server, and how to install and configure CoovaAP on a wireless router.

4.1. MikroTik

General network configuration:

### an address on the outside (WAN) interface of the mikrotik/ ip address add address=192.168.35.100/24 interface=ether1

### add a gateway# / ip route add gateway=192.168.35.1

### set the DNS servers/ ip dns set primary-dns=192.168.35.11 secondary-dns=4.2.2.2

Radius configuration:

### add another address for connecting to the radius server/ ip address add address=192.168.25.121/24 interface=ether2

### add radius servers for any PPP service on mikrotik/ radius add service=hotspot address=192.168.25.101 secret=radiussecret timeout=2000ms

/ radius incoming set accept=yes

Setup masquerading:

### setup NAT on the outside interface of the mikrotik/ ip firewall nat add chain=srcnat out-interface=ether1 action=masquerade

### disable masquerading for the radius LAN (192.168.25.0/24)/ ip firewall nat add chain=srcnat out-interface=ether1 \ src-address=192.168.25.0/24 action=return/ ip firewall nat print/ ip firewall nat move 1 0

Add a pool:

### add a pool/ ip pool add name=pool0 ranges=192.168.10.0/16

Add a hotspot server profile:

/ ip hotspot profile add name="prof1" hotspot-address=192.168.10.1 dns-name="hotspot1.al" html-directory=hotspot use-radius=yes radius-accounting=yes

Add a hotspot server:

/ ip hotspot add name="server1" interface=ether2 address-pool=pool1 profile=prof1

Add a user profile:

/ ip hotspot user profile add name="userprofile1" address-pool=pool1 transparent-proxy=no

Add a user:

/ ip hotspot user add server=server1 name="user1" password="passw1" profile=userprofile1

Modify the hotspot login pages.

4.1.1. Referencies

http://www.mikrotik.com/testdocs/ros/2.9/ip/hotspot.php

http://www.mikrotik.com/testdocs/ros/2.9/guide/aaa_hotspot.php

4.2. ChilliSpot

4.2.1. Introduction

ChilliSpot is used as an access point controller in a wireless LAN. A typical network architecture is shown in the figure below. A wireless client can establish a wireless connection to an access point, but in order to reach the External Network it first has to authenticate with Chilli.

Three different networks are involved in the architecture:

External Network . The external network is typically the Internet or a corporate intranet. Access to the

external network is guarded by Chilli which only allows traffic from authenticated wireless clients to pass.

Internal Network . The internal network is connecting the access points with Chilli. It is used for forwarding Ethernet frames between Chilli and the wireless clients as well as for IP management traffic to and from the access points.

Wireless Network : The wireless clients are connected to the wireless network, and the access points serve as bridges between the internal network and the wireless network. This enables forwarding of Ethernet frames between Chilli and the wireless clients. In the example above the wireless network is allocated the address range 192.168.182.0/24.

In order to function properly Chilli depends on a few external servers:

DNS Server . When accessing the external network the wireless clients rely on one or several DNS servers for resolving domain names to IP addresses. The wireless clients are informed of the DNS server IP addresses by the Chilli. Before you start the installation of ChilliSpot you need to determine the IP address of at least one DNS server which can be used by the wireless clients. If you don't specify a DNS server Chilli will use the DNS server which is reported by the underlying operating system.

UAM Server . When a user logs on he is redirected to an authentication web server which queries the user for her username and password. If a separate uam server is not available it is possible to install one on the Chilli server.

Radius Server . User credentials are stored in one or several radius servers. Whenever a wireless client attempts to connect to the network Chilli will contact a radius server in order to validate the user credentials. If a separate radius server is not available it is possible to install one on the Chilli server.

Generally the access points should be configured with open authentication and no encryption. Authentication is handled by Chilli. For better security, the access points should be configured for Wireless Protected Access.

4.2.2. Installing and Configuring

Download from http://www.chillispot.info/download.html the latest RPM package and install it with the command:

rpm -Uhv chillispot-1.1.0.i386.rpm

During installation of ChilliSpot a configuration file was copied to /etc/chilli.conf . You need to edit this file. A description of each option is given in the man page ( man chilli ). As a start you can leave most of the parameters as they are.

If you use an external radius server you need to modify the parameters: radiusserver1 , radiusserver2 , radiussecret . If you are not using an external radius server you can leave these parameters as they are, as we will install a radius server later during the installation.

If you use an external UAM server you need to modify the parameter uamserver . If you are

not using an external UAM server you can leave this parameters as it is, as we will install an UAM server later during the installation.

In order to automate startup of chilli issue the command:

chkconfig chilli on

ChilliSpot will start next time you reboot the system, or you can start it directly by issuing the command

service chilli start

4.2.3. Firewall Setup

It is important to protect ChilliSpot from unauthorized traffic. No single firewall ruleset can satisfy all network configurations, and generally you should write your own set of rules. As a starting point you can use the script located in: /usr/share/doc/chillispot-1.1.0/firewall.iptables . You can edit this file to suit your own configuration or simply use it without modification.

Once you have edited the file install it by issuing the following commands:

service iptables stop/usr/share/doc/chillispot-1.1.0/firewall.iptablesservice iptables save

This will first clear the current firewall rules, install the new rules and finally save the rules so that they will be restored whenever the system is rebooted.

In order for ChilliSpot to forward network packets, IP forwarding must be turned on in the kernel. You need to change this line in /etc/sysctl.conf :

net.ipv4.ip_forward = 1

The changes take effect when you reboot the system, or you can activate them directly by issuing the command

/sbin/sysctl -p

4.2.4. UAM Authentication Web Server

We will now configure Apache to request username and password from the wireless clients:

During installation of ChilliSpot a cgi script was placed in /usr/share/doc/chillispot-1.1.0/hotspotlogin.cgi . Copy this script to /var/www/cgi-bin/hotspotlogin.cgi on the web server.

We need to tell Chilli about the location of the authentication server. This is done by uncommenting and editing the following line in /etc/chilli.conf :

uamserver https://192.168.182.1/cgi-bin/hotspotlogin.cgi

We need to restart chilli in order for the configuration changes to take effect:

service chilli restart

4.2.5. Configuring FreeRADIUS

We will now configure FreeRADIUS to authenticate the HotSpot users.

Insert users in the radius database.

Edit raddb/clients.conf in order to configure the IP address and shared secret of chilli. The secret must match the radiussecret parameter in /etc/chilli.conf.

Tell Chilli about the location of the radius server. This is done by uncommenting and editing the following lines in /etc/chilli.conf :

radiusserver1 127.0.0.1radiusserver2 127.0.0.1radiussecret testing123

Restart chilli in order for the configuration changes to take effect: service chilli restart.

4.2.6. Referencies

http://www.chillispot.info/download.html

http://www.chillispot.info/release.html#mozTocId867888

http://global.freifunk.net/item/chillispot_howto

4.3. CoovaChilli

4.3.1. Introduction

CoovaChilli is an open-source software access controller, based on the popular ChilliSpot project. It is a feature rich software access controller that provides a captive portal / walled-garden environment and uses RADIUS for access provisioning.

4.3.2. Installing

From a RPM package:

wget http://ap.coova.org/chilli/coova-chilli-1.0.11-1.i386.rpmsudo rpm -U coova-chilli-1.0.11-1.i386.rpm

Building from source:

wget http://ap.coova.org/chilli/coova-chilli-1.0.11.tar.gztar xzf coova-chilli-1.0.11.tar.gzcd coova-chilli-1.0.11./configuremakesudo make install

Building the last version from SVN:

svn checkout http://dev.coova.org/svn/coova-chilli/cd coova-chilli sh bootstrap./configuremakesudo make install

By default it will be installed on /usr/local/ .

4.3.3. Configuration

Go to /etc/chilli/ (or /usr/local/etc/chilli/ ) and make a copy of defaults to config :

cd /etc/chilli/cp defaults config

Modify /etc/chilli/config like this:

#### Local Network Configurations

#

HS_WANIF=eth0 # WAN Interface toward the InternetHS_LANIF=eth1 # Subscriber Interface for client devicesHS_NETWORK=10.1.0.0 # HotSpot Network (must include HS_UAMLISTEN)HS_NETMASK=255.255.255.0 # HotSpot Network NetmaskHS_UAMLISTEN=10.1.0.1 # HotSpot IP Address (on subscriber network)HS_UAMPORT=3990 # HotSpot Port (on subscriber network)

#### HotSpot settings for simple Captive Portal#

HS_UAMSECRET=

HS_RADIUS=192.168.25.101HS_RADIUS2=192.168.25.102HS_RADSECRET=test

HS_NASIP=192.168.35.46 # To explicitly set NAS-IP-Address

# The server to be used in combination with HS_UAMFORMAT to # create the final chilli 'uamserver' url configuration.HS_UAMSERVER=192.168.25.100

# Use HS_UAMFORMAT to define the actual captive portal url.# Shell variable replacement takes place when evaluated, so here# HS_UAMSERVER is escaped and later replaced by the pre-defined # HS_UAMSERVER to form the actual "--uamserver" option in chilli.HS_UAMFORMAT=http://\$HS_UAMSERVER/uam/

# Same principal goes for HS_UAMHOMEPAGE.HS_UAMHOMEPAGE=http://\$HS_UAMLISTEN:\$HS_UAMPORT/www/coova.html

HS_LOC_NAME="HotSpot1" # WISPr Location Name and used in portal

Caution: Be sure to leave empty HS_UAMSECRET, since we are going to use the JSON interface , otherwise the users will fail to login .

Start the chilli service:

chkconfig chilli onchkconfig --list chilliservice chilli startservice chilli status

When the service is started, it will automatically create the configuration files hs.conf, local.conf and main.conf from config . When the config is modified, the chilli service must be restarted as well.

In the config file we have defined the uamserver like this:

HS_UAMSERVER=192.168.25.100HS_UAMFORMAT=http://\$HS_UAMSERVER/uam/

This is a webserver different from the server where coova-chilli is installed. In this server we have to create an index.html file:

mkdir -p /var/www/html/uam/cd /var/www/html/uam/wget http://coova.org/uam/wget http://coova.org/js/chilli.js

Then, we should edit index.html to use chilli.js from local. We can also modify index.html as we like.

Note: The authentication page http://192.168.25.100/uam/index.html can actually be any page, enough that it contains the line:

<script id='chillijs' src='chilli.js'></script>

For more details see Any page a login page .

4.3.4. Referencies

CoovaChilli

CoovaChilli Documentation

CoovaChilli Development

CoovaChilli HowTo

CoovaAAA Captive Portal

CoovaChilli Forum

Any page a login page

CoovaChilli JSON Interface

4.4. CoovaAP

4.4.1. Introduction

CoovaAP Firmware is a linux system that can be installed in a wireless router. In this system are included several packages/tools that extend and enhance the features of the router. CoovaAP is an OpenWRT-based firmware designed especially for HotSpots. It comes with the CoovaChilli access controller built-in and makes it easily configurable. CoovaAP is perfect for just about any HotSpot application - from WPA Enterprise (with RADIUS accounting) to Free WiFi with Terms of Service acknowledgment to commercial HotSpot captive portal applications. The configuration of the router is managed through a web-interface, but it is also possible to login via ssh into the router.

The wireless routers that are supported by CoovaAP are: Linksys WRT54GL, Linksys WRT54G, Linksys WRT54GS, Linksys WRT54GS v4, etc.

The key features of CoovaAP are:

Open-source, based on OpenWrt

Advanced Web-based Configuration

Easy HotSpot Configuration & Status

CoovaChilli Access Controller

Embedded Captive Portal

Facebook HotSpot Captive Portal

Integrated CoovaChilli with WPA

OpenID Authentication

Centralized CoovaChilli Configuration

WiFiDog Access Controller

PPTP VPN Client and Server

OpenVPN Client

Traffic Shaping

WDS HotSpot

For more details look at the CoovaAP homepage.

4.4.2. Installing

The installation is described very well in the page CoovaAP Firmware Installation http://coova.org/wiki/index.php/Installation_Help.

4.4.3. Configuration

At System / Settings :

System Settings Host Name : LinkSys boot_wait : Enabled Language : English System Administration WAN SSH Access : Enabled WAN Web Access : HTTPS Only HotSpot SSH Access : Enabled

HotSpot LAN Web Access : HTTPS Only

At Network / DHCP :

DHCP Settings LAN DHCP Services : Enabled Starting Address : 192.168.1.100 Number of Addresses : 150

At Network / WAN :

WAN Configuration Connection Type : Static IP IP Settings IP Address : 192.168.25.31 Netmask : 255.255.255.0 Default Gateway : 192.168.25.1

DNS Servers 192.168.25.101 4.2.2.2

At Network Wireless :

Wireless Configuration Wireless Interface : Enabled ESSID Broadcast : Show ESSID : WiFi Channel : 11 Mode : Access Point

Encryption Settings Encryption Type : Disabled

At Network / Advanced Wireless :

Settings Isolate WLAN clients : Enabled

At HotSpot / Configuration :

HotSpot Configurations HotSpot Type : ChilliSpot UAM HotSpot Mode : LAN & Wireless

ChilliSpot Configurations Auto Configuration : Web URL Web Config URL : http://192.168.25.100/hotspot/config/

At HotSpot / Location :

Hotspot Location

Location Name : Location Location Address : Address Network Name : Network Country ISO Code : AL

4.4.4. Radius Configuration

In the interface HotSpot / Configuration we have these settings:

HotSpot Configurations HotSpot Type : ChilliSpot UAM HotSpot Mode : LAN & Wireless ChilliSpot Configurations Auto Configuration : Web URL Web Config URL : http://192.168.25.101/hsconfig/

The configuration of ChilliSpot (coova-chilli) is retrieved from the server 192.168.25.101 by http. The configuration file index.html in this server has this content:

uamserver http://www.example.net/hs/radiusserver1 192.168.25.101radiusserver2 192.168.25.102radiussecret secretpasswradiusnasid HotSpotuamallowed www.example.net

It contains the configuration of the radius server. The parameter uamserver contains the URL of the web page that will be used by the clients to login to internet.

In case that the configuration is different for different routers, then the setting Web Config URL should be different, so that they can load different configurations. This can be useful if we want to have a different radiusnasid for different routers and a different (personalized) login page.

4.4.5. Login Page

The login page that is located at http://www.example.net/hs/ consists of an html and a javascript file, as described at CoovaChilli JSON Interface .

The content of the file index.htm is this:

<html><head><!-- A purely HTML based captive portal using the JSON interface of CoovaChilli--><title>coova hotspot</title><style><!--body,td,a,p,h{ font-family:arial,sans-serif;}body {

text-align: center; padding-top: 30px; margin: auto; width: 50%;}#MyChilli { background: url("coova.jpg") right top no-repeat; margin: auto; text-align: left; padding: 10px 0 30px 0;}#locationName { height: 50px; font-size: 120%; font-weight: bold;}#chilliPage { border: 1px solid orange; padding: 20px 20px 20px 20px; margin-top: 20px;}#signUpRow { display: inline;}--></style></head><body><div id="MyChilli">

<div id="noLocation" style="display:none;"><p style="padding-top: 100px;"><strong>You are not at a hotspot.</strong> If you want to see a a sample login page using the <a href="http://coova.org/wiki/index.php/CoovaChilli/JSON">JSON interface</a> of <a href="http://coova.org/wiki/index.php/CoovaChilli">CoovaChilli</a>, then <a href="javascript: window.location = 'view-source:' + window.location.href;">view the source</a> of this page.</p></div>

<h1>Homepage</h1><script id='chillijs' src='chilli.js'></script>

</div></body></html>

The content of the file chilli.js is this:

if (navigator.appVersion.indexOf("MSIE")!=-1)document.write("<script type='text/javascript' id='chillicontroller'></script>");

if (!window.queryObj) { window.queryObj = new Object(); window.location.search.replace(new RegExp("([^?=&]+)(=([^&]*))?","g"), function($0,$1,$2,$3) { queryObj[$1] = $3; });}

if (queryObj['uamip'] != null && queryObj['uamport'] != null) { var script = document.getElementById('chillicontroller');

if (script == null) { script = document.createElement('script'); script.id = 'chillicontroller'; script.type = 'text/javascript'; script.src = 'http://'+queryObj['uamip']+':'+queryObj['uamport']+'/www/chillijs.chi';

var head = document.getElementsByTagName("head")[0]; if (head == null) head = document.body; head.appendChild(script); } script.src = 'http://'+queryObj['uamip']+':'+queryObj['uamport']+'/www/chillijs.chi';} else { var noLocation = document.getElementById("noLocation"); if (noLocation != null && noLocation.style) { noLocation.style.display = 'inline'; }

4.4.6. Quick Config

After a CoovaAP wireless router has been configured properly, its configuration can be backup-ed in order to use it for quick reconfiguration of the device. The configuration can be downloaded and uploaded at the interface System / Config Management .

The configuration backup can also be used to configure quickly a new router. In this case, these configuration settings should be modified manually:

IP Address at Network / WAN has to be modified.

HotSpot / Location can be modified.

Web Config URL at HotSpot / Configuration can be modified optionally, in case that we want to provide a customized login page, radius server, etc.

4.4.7. Referencies

CoovaAP Firmware

CoovaAP Firmware Installation

CoovaChilli JSON Interface

CoovaAP Forum

5. GNU Free Documentation License

Version 1.2, November 2002

Copyright (C) 2000,2001,2002 Free Software Foundation, Inc.

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