Alternative to autofs to mount CIFS folders in user home folders in multi-user environment

Question

My use case seems very simple. I want to automount CIFS folder CIFS1 and CIFS2 which exist for all users on my fileserver in each user home during login on this multi-user 18.04 Ubuntu machine.

So if user1 login, i mount :

• /home/user1/CIFS1
• /home/user1/CIFS2.

If user2 login, i mount :

• /home/user2/CIFS1
• /home/user2/CIFS2.

I have an already a working mounting command to do this, using Kerberos ticket / SSSD to authenticate :

sudo mount -v -t cifs -o user=${USER},cruid=${USER},sec=krb5,uid=${UID} //isilon.mydataserver/CIFS1/${USER} /home/${USER}/CIFS1

sudo mount -v -t cifs -o user=${USER},cruid=${USER},sec=krb5,uid=${UID} //isilon.mydataserver/CIFS2/${USER} /home/${USER}/CIFS2

Works well, but now i want to automount these folders directly after login, with correct ${USER} information injected into autofs configuration.

And ... it seems impossible, i try many things, direct or indirect mapping, executable automap, without success.

The [mountpoint] [option] [location] pattern of autoconf files accept injection of environnement variable (USERS, UID, etc.) only in the option/location part.

In sudo nano /etc/auto.master i have :

/- /etc/auto.cifs --ghost

Following the sun autofs pattern for direct mounting : [mountpoint] [option] [location], my /etc/auto.cifs config contain :

/home/${USER}/CIFS1 -fstype=cifs,user=${USER},cruid=${UID},sec=krb5,uid=${UID} ://isilon.mydataserver/CIFS1/${USER}

/home/${USER}/CIFS2  -fstype=cifs,user=${USER},cruid=${UID},sec=krb5,uid=${UID} ://isilon.mydataserver/CIFS2/${USER}

Reloading configuration :

sudo systemctl reload autofs

During users login, this configuration create litteraly a /home/${USER}/CIFS1 folder and not an /home/user1/CIFS1 or /home/user2/CIFS1 folder ...

Is there a way to obtain this behavior (mounting CIFS folder into multi-users environment : /home/$USER with $USER = user1, user2, ...) using autofs, or another method compatible with Kerberos / SSSD / CIFS authentification ?

Edit1 : I precise to readers that i cannot modify the Active Directory schema in place to use the automounting function of SSSD/AutoFS :(

Edit2 : I also try to run bash program from auto.master with program:/etc/auto.cifs , but it seems that doesn't answer to this problem because program could only return the [option][location] and not the [mountpoint] part.