PAM: change user's passwords in the Freeradius server

[Roberto Carna]

Dear, I have a Freeradius/Mysql server that authenticates SSH logins
from Debian machines.

In the Freeradius I add the user and password basically, and in each
Debian machine I have installed the libpam-radius-auth package in
order to execute SSH and SUDO, all authenticating against the
Freeradius server.

But now I want the Debian machines' users to change their passwords
with the "passwd" command in the MySQL database from Freeradius, but
after editing the file /etc/pam.d/passwd as follow:

password              sufficient pam_radius_auth.so     debug
@include common-password

the users can't change their passwords at all in the Freeradius server.

As I said, the SSH login and SUDO command work perfectly
authenticating against Freeradius, this is my /etc/pam.d/sudo file:

auth                  required pam_radius_auth.so     debug
account               required pam_radius_auth.so     debug
password              required pam_radius_auth.so     debug

How can I edit the /etc/pam.d/passwd file in order to let users to
change Freeradius passwords???

Thanks a lot,

Roberto