This document covers IS4C authentication and general security tips.
Almost all of this is optional, and there are certainly existing stores
ignoring different parts of it to no real ill effect. IS4C does not store
any particularly sensitive information, and there are [unfortunately] far
easier ways to steal from a retail establishment than breaking into the POS.
A firewall is your first line of defense. There's no reason to allow any
one but your staff access to Fannie or POS. Regardless of what firewall software
you use, keeping the public off your network is recommended.
Putting employee workstations and front end POS on different subnets is
recommended, if possible. The easiest way to accomplish this is to use a
machine with two NICs for your Fannie server. If the workstation network is
192.168.1.x and the POS network is 192.168.2.x, the server is accessible
from both without allowing any traffic from one subnet to the other.
Front End Authentication
Authentication at the registers is fairly simplistic. Employees are
assigned a numeric passcode (via Fannie's Admin => Cashier Management menu item).
Front End employees are subdivided into two tiers of access. Regular cashiers
can only log into a lane if the lane is not currently in use. Manager cashiers
can always log into a lane, even if someone else is already logged in. Primarily, the
higher level is used when a regular employee goes home for the day without
logging out properly.
Back End Authentication
First and foremost, Fannie's authentication system is optional. If you run into
headaches, you can always turn it off. You can also ignore it entirely if you
Fannie relies on a more elaborate authentication systems. Users log in with a user
name and password. Rather than arrange users in tiers, access is granted on a
per-task basis. This is for maximum flexibility; one user might have permission
to edit products but not members while another might have permission to edit
members but not products.
To get started with authentication, follow the Authentication link on
Fannie's configuration. First set Authentication Enabled to Yes (ignore
the other options for now; they'll be covered later). User accounts and permissions
are stored in the database. After authentication is enabled, if no users exist
you will be prompted to create an initial user. Enter a username and password.
If nothing goes wrong, that user will be created with admin privileges.
With an admin account created, go to the user account administration section,
http://localhost/fannie/auth/ui/ (substituting a correct host name and path
to fannie if needed). Log in and you get a big menu of options. You can:
Creating and deleting users is pretty straightforward. Authorizations are the permission
system. The authorization class refers to the task, and optional subclasses allow further
refinement. For example, the authorization class admin (subclass all, all) grants
access to all these user / authorization / group tools. GIANT TODO: make list of existing
auth classes in fannie...
While task based permissions are flexible, they're also a bit unwieldy if someone needs
a lot of access. Arranging users into groups helps alleviate this. Assigning an authorization
to a group is the same as adding the authorization to each of the groups member's individually.
Similarly, adding a user to a group gives that user all the authorizations assigned to that
Now, about those other configuration options. User permissions are always stored in
the database, but there are a few options for validating username and password combinations.
- View existing users, create new ones, and delete users
- View authorizations for a user, assign new authorizations, or delete existing ones
- Manipulate groups
- Switch to another user (useful for testing/troubleshooting other people's accounts)
Shadow and LDAP authentication are both optional; if you don't have existing accounts to re-use,
SQL authentication works fine. The only disadvantage is it's yet another set up process
for users to go through and yet another password to remember. If you do use shadow or LDAP, keep
in mind that accounts are imported into the database passively - i.e., when a user logins in the
first time, that account is imported - rather than all at once.
- SQL. User passwords (hashes) are stored directly in the database. This one's mandatory.
- Shadow. This option matches usernames and passwords against entries in the /etc/shadow file.
This is a Linux-only option. If the server is providing other services - e.g., email, samba, etc -
and already has user accounts, Fannie can use those. This option relies on the included
shadowread utility. If the config page reports any errors with shadowread, just recompile
and install it (very simple. make, sudo make install)
- LDAP. This options checks usernames and passwords against an LDAP server. The defaults
are tailored to openldap, but in theory you can use any LDAP server provided the field
names are correct. Active Directory is obviously the other major option; if someone figures
out appropriate field names for AD, they'll be added here as suggestions.
You may not want the web-based install/config pages accessible to everyone (in practice, this has
never been an issue). Fannie includes a shell script, secure.sh, in the install directory that will
generate a username/password combo and apply it to that directory. If this results in a 500 Internal
Server error, you most likely need to add AuthConfig to your main apache config's
AllowOverride line. Copy the same script to lanes' install directory and re-run if the same restriction
is desired there.
Windows folks: the script creates an .htaccess that looks like this:
AuthName "Fannie Config"
Correct the path for password file as needed. You're on your own to figure out
how to actually create a htpasswd file on Windows. Maybe there's a command for it