Authentication Modules

Authentication modules are used by various NetWin Ltd products which include:

These products use the external module to determine what accounts are valid and they can be used to store other useful information about the user like disk quota.

The modules that are displayed on this page are ones that we currently provide. Since all the modules follow the same 'Authentication Protocol', you can write your own modules to interface with the database that you wish to use. You can also contact NetWin Ltd if you wish us to write the module for you. If you have any questions or need to know more about any aspect of authentication modules please Email:



There are many different types of external authentication modules, some do have their limitions due to the interface to the database being used. Each is explained in the sections that follow.


The diagram to the right displays the overall view of where the external authentication modules fits compared with the main application (like SurgeMail and DNews) and the database where the user information is stored.

The protocol that the main application uses to talk to the external authentication module is defined in the 'Authentication Protocol' section of this manual. Not all modules will support all protocols due to limitions on accessing data in the main database.

This manual will not deal with any information about how to interface the external auth module with the final target database. There is plenty of information on the internet which would help you in this.


The biggest advantage of setting up the external module like this, is that if we do not have a module to interface with your target database you can write your own module following the 'Authentication Protocol'.

Modules Currently Available

There are many different types of external authentication modules available. Each module is describe in the following table. If you click on the name of the module it will take you to a page giving more deatils about that module.

Link for Details



This external authentication module comes in all distribution sets. The source is provided on all platforms and for Windows and most UNIX based platforms it is pre-compiled, as nwauth.exe or nwauth.

This module is the default module that most NetWin Ltd products use. This uses a simple text file were all the user information is stored. All passwords are encoded using 'crypt'.

This is our recommendation.

UNIXAuth UNIXAuth should ONLY be used if you have an existing mail server whose email accounts are in fact UNIX user accounts, it should not be used otherwise UNLESS you want to give your email users a shell account on your UNIX system.

UNIXAuth will only work if run as root. You can force it to run as root even if the application calling it isn't.

chown root:root unixauth
chmod 6775 unixauth


NTAuth is version simular to that of UNIXAuth except that the module only works on Windows systems.

This module should ONLY be used if you have an existing mail server whose email accounts are in fact Window user accounts.


This module allows your user information to be stored in an LDAP database. LDAPAuth should work with any v2 or v3 complient LDAP server.

Recommended LDAP servers:
SurgeLDAP (By Netwin Ltd)

This module interfaces with a MySQL Database.

Recommended MySQL servers:

This module allows you to authenticate with several modules simultaneously based on wild card matching and other rules.

This allows you to setup 1 (or more) domains each using a different database. For example you could setup 2 domains where each domain has seperate LDAP databases. So you setup two LDAPAuth within MultiAuth.


This is our module to talk to an Oracle user database.

PAMAuth This is the module to talk to the a Linux PAM module.
RadiusAuth This is the module to talk to the a Linux Radius module.
DNAuth This is a modified verison of NWAuth which can check and lookup users from a DNews users.dat file.

Our authentication module for talking to an ODBC Driver for a Database (e.g. MS Access, MS SQL Server, ORACLE)

This is only available for Windows NT/2000/XP systems.

TCPAuth TCPAuth is a TCPIP client+server module that will take any other module as its backend. Allows easy authentication across boxes and across platforms.
POPAuth POPAuth is a POP proxy authentication module. Allows one or more POP servers to be used for authenticating users.
HTTPAuth HTTPAuth is an HTTP proxy authentication module.