Package tcb: Information

This package consists of three components: pam_tcb, libnss_tcb, and
libtcb.  pam-tcb is a PAM module which supersedes pam_unix.  It also
implements the tcb password shadowing scheme (see tcb(5) for details).
The tcb scheme allows many core system utilities (passwd(1) being the
primary example) to operate with little privilege.  libnss_tcb is the
accompanying NSS module.  libtcb contains code shared by the PAM and
NSS modules and is also used by programs from the shadow-utils package.