libpam-ssh binary package in Ubuntu Xenial i386

 This pluggable authentication module (PAM) provides single sign-on
 using secure shell (SSH) keys:
 - during authentication, the user types a SSH passphrase and is authenticated
   if the passphrase successfully decrypts the user's SSH private keys;
 - in session phase, a ssh-agent process is started and decrypted keys are
   added, and thus the user can SSH to other hosts that accept key
   authentication without typing more passwords for the entire session.

Source package