Currently, the Corporate Directory tool only supports Cisco directories, and the targets file entries are based in part on directory entries; however, there are many fun possibilities for using the targets.txt file in creative ways. Directory entries are less likely to change for an extension than are the IP address for an IP Phone that is mapped to an extension. In UCSniff Learning Mode, targets are still mapped to the 'targets.txt' file independent of a directory entry. The targets.txt file just won't include the directory entry if it wasn't downloaded. Therefore, you can create your own targets.txt file and customize directory names!
If you are a pentester (or whoever you are ;-) ), you can use the same method that an internal user follows in order to find an extension. People don't call random numbers until they get the person they are trying to reach. They either have a utility in the phone, a corporate Intranet web application, or something printed up in hard copy to lookup users. Whatever the method, the pentester just uses the same method. If you don't know, simply play dumb and ask an internal user. You can then import these entries into targets.txt, or manually edit the file.
When you run the tool in learning Mode, you'll see the format of the extensions as decoded in the SIP URI. These entries will be maped into targets.txt. Then you can run the tool in Target Mode to *target* specific users. The format of the targets.txt file is:
IP,extension,name,protocol
So you can use your imagination on how to use this file,it has some great possibilities for fun. Here are two sample entries:
bt src#cat targets.txt
172.16.96.18,1004,John (CEO) Rodgers,sccp
172.16.96.12,1090,Eric Winsborrow,sccp
bt src#
You don't always have to run Learning Mode. If you know for certain the IP address and extension for a given endpoint, you never have to run "Learning Mode" - run "Target Mode" instead. You can set up UCSniff 'targets.txt' manually to ARP Poison and intercept only the endpoint traffic you are looking to inspect.