[OpenSER-Devel] New LDAP module

[Christian Schlatter]

Hi all,

I am a member of the ITS Telecommunications R&D team at the University 
of North Carolina, and we would like to contribute a new LDAP module for 
the openser SIP server.

This new module implements an LDAP search operation interface for 
openser and allows to import data from an LDAP directory into the 
openser script variable space.

The following features are offered by this module:

   * LDAP search function taking an LDAP URL as input
   * LDAP result parsing functions to store LDAP data as AVP
   * Support for accessing multiple LDAP servers
   * LDAP SIMPLE authentication
   * LDAP server failover and automatic reconnect
   * Configurable LDAP connection and bind timeouts
   * Module API for LDAP search operations that can be used by other 
OpenSER modules

This is the first of two modules we'd like to contribute to the openser 
project. The other module, called H350, is using the LDAP module API in 
order to implement an ITU-T H.350 interface for openser. H.350 is an 
emerging ITU-T standard that defines how SIP (and other RTC protocol) 
account data is stored in an LDAP directory. We are working together 
with other companies who are very interested in this feature as well. 
The H350 module is not yet ready for contribution.

We are using these modules in production since about two months and had 
no issues so far. Performance measurements have shown that this LDAP 
interface is very fast. We could achieve better call rates than with MySQL.

It might be worth to consider using the LDAP module API for other 
modules as well, like e.g. the proposed auth_ldap. The LDAP module 
handles all LDAP connection and configuration related issues, whereas 
the module using the LDAP module API only has to care about the specific 
LDAP search operation.

The source code of this new LDAP module is available at

https://sourceforge.net/tracker/index.php?func=detail&aid=1748544&group_id=139143&atid=743022

  Please have a look at the code and documentation and let me know your 
thoughts. We'd be glad to commit maintaining these modules for at least 
one year.


thanks,
Christian