Exec-Program-Wait vs rlm_exec vs rlm_<your own>

[Doug Hardie]

I transitioned from Cistron radius some time ago.  There the only  
option was Exec-Program-Wait.  I had developed one that suited our  
needs.  It transitioned quite well to freeradius.  However, there are  
notes in various places that Exec-Program-Wait will somtime go away.   
The indicated replacement is rlm_exec.  I tried to convert my  
programs over to that and never could quite get everything to work.   
There were always issues that have been discussed here at length.   
There were some patches that might have helped my situation, but I  
didn't want to have to keep remembering to patch new versions etc.

Recently I took a more detailed look at rlm_example and decided to  
give that approach a try.  Its actually quite easy to convert an Exec- 
Program-Wait into a rlm_xxxx.  Some of the steps are not obvious and  
the really difficult part is figuring out what you need to do to get  
configure to work properly.  The real advantage of this, however, is  
that there is no forking overhead.  It runs a lot more efficiently  
and can do more than what the Exec-Program-Waits can do.  Hence, I  
would suggest that rather than push the rlm_exec as the replacement  
for Exec-Program-Wait, that creating your own rlm_xxxx would be a  
better approach.

There are no real instructions for creating your own rlm that I could  
find.  However, the experience is still fresh and if you are  
interested I could put together a first draft of instructions on  
creating a rlm.