table of contents
SHADOW(5) | File Formats and Configuration | SHADOW(5) |
NOME¶
shadow - file delle password shadow
DESCRIZIONE¶
shadow is a file which contains the password information for the system's accounts and optional aging information.
Questo file non deve essere leggibile dagli utenti normali se si vuole mantenere la sicurezza sulle password.
Each line of this file contains 9 fields, separated by colons («:»), in the following order:
login name
encrypted password
If the password field begins with an exclamation mark !, the password is locked. The remaining characters on the line represent the password field before the password was locked.
Refer to crypt(3) for details on how this string is interpreted.
If the password field contains a string that is not a valid result of crypt(3), for instance ! or *, the user cannot use a UNIX password to log in. However, the user may log in the system by other means.
date of last password change
The value 0 indicates that the user must change their password the next time they log in to the system.
Un campo vuoto implica che la scadenza della password è disabilitata.
minimum password age
An empty field and value 0 mean that there is no minimum password age.
maximum password age
After this number of days has elapsed, the password may still be valid. The user is prompted to change their password at the next login.
Un campo vuoto indica che non ci sono una età massima password, un periodo di avviso e nessun periodo di inattività (vedere oltre).
Se l'età massima password è minore dell'età minima password, l'utente non può cambiare la propria password.
password warning period
An empty field and value 0 mean that there is no password warning period.
password inactivity period
After the password expires and the password inactivity period elapses, the user cannot log in and must contact their administrator.
An empty string means that no inactivity period is enforced.
account expiration date
Note that account expiration differs from password expiration. Account expiration prevents the user from logging in, whereas password expiration only prevents users from logging in with their password.
An empty field means that the account never expires.
The value 0 should not be used, as it is interpreted either as an account with no expiration or as an expiration date of 1970-01-01.
reserved field
FILE¶
/etc/passwd
/etc/shadow
/etc/shadow-
Notare che questo file viene usato dagli strumenti del pacchetto shadow, ma non da tutti gli strumenti per la gestione di utenti e password.
VEDERE ANCHE¶
chage(1), login(1), passwd(1), passwd(5), pwck(8), pwconv(8), pwunconv(8), su(1), sulogin(8).
26/08/2025 | shadow-utils 4.18.0 |