[Linux] Automounting NFS using PAM_EXEC

Linux - Using PAM_EXEC to mount userspaces

PAM_EXEC - What is it?

On a Linux box, users are authenticated via a PAM module. These modules check passwords, and do tasks before the shell is presented.
PAM_EXEC will allow you to run a script when the user logs on/out or changes passwords.

My Mission

The main aim was to mount a NFS space under the users $HOME directory when they login. This allows for shared storage to be used and no-matter what server the user logs in to, their NFS shares are present.

My script

A file named  /usr/local/bin/mounthome.sh with the below contents. Set the file permissions to execute using chmod +x /usr/local/bin/mounthome.sh

Change the mount server and volumes to suit your own server needs. The below will create a directory called nfs and mount the NFS server under it

 

#!/bin/bash
#   
#        "User: $PAM_USER"
#        "Remote Host: $PAM_RHOST"
#        "Service: $PAM_SERVICE"
#        "TTY: $PAM_TTY"

if [ "$PAM_TYPE" == "open_session" ]
then
        mkdir /home/$PAM_USER/nfs
        mount -t nfs -o user server.local:/volume1/$PAM_USER /home/$PAM_USER/nfs
        chmod 777 /home/$PAM_USER/nfs
        chown $PAM_USER:$PAM_USER /home/$PAM_USER/nfs
fi

if [ "$PAM_TYPE" == "close_session" ]
then
        umount /home/$PAM_USER/nfs
fi

exit 0

Executing it using PAM

Modify /etc/pam.d/common-session file accordingly:

session    optional     pam_exec.so    /usr/local/bin/mounthome.sh

And thats all it takes!