Compiling modules

Jonathan Anthony jonathan.anthony at
Mon Nov 27 11:01:57 CET 2017

Thank you Alan for your help.
I am still a little confused.  What we are doing is that we have a secure box for storing, initially usernames and passwords using our own built hardware/software.
1.  We want to write a "plug-in" which I assume will be a module, so that when authenticating a user, it will send a command to our box. The box returns simply yes or no depending if the password matches. I thought rlm_pap authenticates using the flat users file. So we assumed that if we modified pap, this would work. Sorry if this is stupid question but I have just started with Radius
2. Say our authentication is called SNAP. How does the radius server select our module to authenticate. I did notice a "hints" file but not sure how this will work.
Many thanks
Jonathan Anthony

-----Original Message-----
From: Freeradius-Devel [ at] On Behalf Of Alan DeKok
Sent: Friday, November 24, 2017 5:01 PM
To: FreeRadius developers mailing list <freeradius-devel at>
Subject: Re: Compiling modules

On Nov 24, 2017, at 10:04 AM, Jonathan Anthony <jonathan.anthony at> wrote:
> I have downloaded the source code and built and installed freeradius 
> server
> 3.0.16 on Ubuntu 17. 
> I want to create new modules. I have only found good info on one site 
> "Creating modules for FreeRADIUS v3.0.x". Any pointers to other sites 
> - I have only just started working with Radius.

  See src/modules/rlm_example/

  It has some example code for doing things.

> My main question, do I have to full radius compile, build and install again.

  That's the easiest way.

> Is there a way of just compiling the module so that the server will 
> pick it up? For example I want to make a small change in the rlm_pap.c 
> file

  If the pre-built binary is from the same source you're using, then you should be able to just modify the module.

  But you can't mix & match from (say) a debian package of 3.0.15, and your own custom rlm_pap.

  And why make changes to rlm_pap?  Unlang can do most of what you need.  And if you need something else, maybe other people need it too, and therefore sending the patches back would be useful.

  Alan DeKok.

List info/subscribe/unsubscribe? See

More information about the Freeradius-Devel mailing list