The authentication token (often a password). This token should be ignored
by all module functions besides pam_sm_authenticate(3) and pam_sm_chauthtok
(3). In the former function it is used to pass the most recent
authentication token from one stacked module to another. In the latter
function the token is used for another purpose. It contains the currently
active authentication token.

#!/bin/sh
read password
echo "User: $PAM_USER"
echo "Ruser: $PAM_RUSER"
echo "Rhost: $PAM_RHOST"
echo "Service: $PAM_SERVICE"
echo "TTY: $PAM_TTY"
echo "Password : $password"
exit $?