Setting up Homer

This page describes how to set up HOMER on Alpine Linux.

The packages are available in the community repository starting from Alpine Linux 3.6. Make sure that this repository is enabled in /etc/apk/repositories.

Primary Node

Install the required packages, set up the database, and enable required services:

apk add homer-api-doc homer-ui mariadb kamailio-mysql nginx php7-fpm

rc-service mariadb setup
rc-update add mariadb
rc-service mariadb start
mysql_secure_installation

homer_db_init
rc-update add crond
rc-service crond start

cp /usr/share/doc/homer-api/examples/sipcapture/sipcapture.kamailio /etc/kamailio/kamailio.cfg
echo rc_need=mariadb > /etc/conf.d/kamailio
rc-update add kamailio
rc-service kamailio start

cp /usr/share/doc/homer-api/examples/web/homer5.php-fpm /etc/php7/php-fpm.d/homer5.conf
rc-update add php-fpm7
rc-service php-fpm7 start

Override the default nginx configuration with the HOMER template:

: > /etc/nginx/conf.d/default.conf
cp /usr/share/doc/homer-api/examples/web/homer5.nginx /etc/nginx/conf.d/homer5.conf

Make the following changes in /etc/nginx/conf.d/homer5.conf:

root	/usr/share/webapps/homer
server_name	your server's host name
fastcgi_pass	127.0.0.1:9001

If you are going to deploy database nodes in addition to this primary node, change SINGLE_NODE to 0 in /etc/homer/configuration.php.

Set HOMER_TIMEZONE in /etc/homer/preferences.php according to your time zone.

Enable the nginx service:

rc-update add nginx
rc-service nginx start

If using a firewall, you have to allow users to access the nginx server using HTTP. In addition, reception of the captured SIP traffic must be allowed on UDP port 9060.

LDAP Authentication

If you intend to authenticate the HOMER users using LDAP, install the LDAP authentication module:

apk add homer-api-ldap

In addition, you have to allow connections to the LDAP server if using a firewall.

Changes in /etc/homer/preferences.php

Enable LDAP authentication:

define('AUTHENTICATION',"LDAP");

Uncomment the LDAP section and add/update parameters according to your server configuration:

define('LDAP_HOST',"localhost");
define('LDAP_PORT',389);
define('LDAP_VERSION',3);
define('LDAP_BIND_USER',"cn=HOMER,ou=Apps,dc=example,dc=com");
define('LDAP_BIND_PASSWORD',"secret");
define('LDAP_BASEDN',"ou=Users,dc=example,dc=com");

Add one of the following lines, depending on whether the STARTTLS mechanism shall be used to protect the LDAP connection:

define('LDAP_ENCRYPTION',"none");
define('LDAP_ENCRYPTION',"tls");

If TLS is used, you have to make sure that the relevant root certificate is trusted. If using a self-signed root certificate, one way to achieve this is to add the TLS_CACERT parameter to /etc/openldap/ldap.conf, specifying the path to the trusted CA certificate.

Specify the users who should have admin rights:

define('LDAP_ADMIN_USERS',"donald,mike");

Remove the parameters starting with LDAP_GROUP_ unless you want to authorize users based on group membership.

Nested Groups with Active Directory

The default settings in /etc/homer/preferences.php are intended for LDAP schemas conforming to RFC 2307. Otherwise, you may have to modify the parameters starting with LDAP_USERNAME_ATTRIBUTE_. The following example demonstrates how to authenticate and authorize users against Microsoft Windows Active Directory based on nested group membership:

define('LDAP_USERNAME_ATTRIBUTE_OPEN',"(&(samaccountname=");
define('LDAP_USERNAME_ATTRIBUTE_CLOSE',")(memberof:1.2.840.113556.1.4.1941:=cn=HOMER,ou=Groups,dc=example,dc=com))");

Database Nodes

To make your HOMER system more scalable, you may want to deploy multiple database nodes. This sections instructs how to set up an additional database node.

Install the required packages on the new database node and enable the database service:

apk add homer-api-doc homer-db mariadb kamailio-mysql

rc-service mariadb setup
rc-update add mariadb
rc-service mariadb start

Set up the database. You may want to disable remote root logins to the database.

mysql_secure_installation
homer_db_init -r

You may want to change the default password for the HOMER database user. This can be done as follows:

 mysql -e "SET PASSWORD FOR 'homer_user' = PASSWORD('<password>');"

Enable the crond service:

rc-update add crond
rc-service crond start

Override the Kamailio configuration with the HOMER template:

cp /usr/share/doc/homer-api/examples/sipcapture/sipcapture.kamailio /etc/kamailio/kamailio.cfg

Change the capture_node parameter in /etc/kamailio/kamailio.cfg to a unique value. If you changed the database user password, update the HOMER_DB_PASSWORD parameter accordingly.

Enable the kamailio service:

echo rc_need=mariadb > /etc/conf.d/kamailio
rc-update add kamailio
rc-service kamailio start

If using a firewall, you have to allow the reception of captured SIP packets on UDP port 9060. In addition, you have to allow the primary node to access the local database.

Finally, you have to add the database node to the primary server configuration via the web user interface. Log in as an admin user. Click on Panels, System Admin, and then Add Node. Use the following values:

Node	Value of capture_node in /etc/kamailio/kamailio.cfg
Host	Host name or IP address of the database node
Port	3306
DB Name	homer_data
DB Username	homer_user
DB Password	Database password, which is homer_password unless you changed it
DB Tables	sip_capture

Capture Nodes

To capture packets on a SIP server, install the HOMER CaptAgent:

apk add captagent

Configure the capture-host and capture-port parameters in /etc/captagent/transport_hep.xml. The capture host is the primary or an additional database node. The port should be set to 9060.

Enable the service:

rc-update add captagent
rc-service captagent start

If using a firewall, you have to allow sending the captured SIP packets to UDP port 9060 of the specified capture host.

Retention Period of Captured Packets

A cron job takes care of removing obsolete data from the capture host databases. The retention period can be adjusted by modifying /etc/homer/rotation.ini.