Provided by: passwd_4.1.1-6ubuntu6_i386 bug

NOME

       newusers - update and create new users in batch

SINOSSI

       newusers [new_users]

DESCRIZIONE

       The newusers command reads a file of user name and clear-text password
       pairs and uses this information to update a group of existing users or
       to create new users. Each line is in the same format as the standard
       password file (see passwd(5)) with the following exceptions:

       pw_passwd
           This field will be encrypted and used as the new value of the
           encrypted password.

       pw_gid
           This field must contain the name (or number) of a group. The user
           will be added as a member to this group. When a non-existent group
           name or number is specified, a new group will be created. In the
           case of a non-existent group number, both the name and the number
           of the new group will be this number.

       pw_dir
           This field will be checked for existence as a directory, and a new
           directory with this name will be created if it does not already
           exist. The ownership of the directory will be set to be that of the
           user being created or updated.

       This command is intended to be used in a large system environment where
       many accounts are updated at a single time.

OPZIONI

       The options which apply to the newusers command are:

       -c, --crypt-method
           Use the specified method to encrypt the passwords.

           The available methods are DES, MD5, NONE, and SHA256 or SHA512 if
           your libc support these methods.

       -r, --system
           Create a system account.

           System users will be created with no aging information in
           /etc/shadow, and their numeric identifiers are choosen in the
           SYS_UID_MIN-SYS_UID_MAX range, defined in login.defs, instead of
           UID_MIN-UID_MAX (and their GID counterparts for the creation of
           groups).

       -s, --sha-rounds
           Use the specified number of rounds to encrypt the passwords.

           The value 0 means that the system will choose the default number of
           rounds for the crypt method (5000).

           A minimal value of 1000 and a maximal value of 999,999,999 will be
           enforced.

           You can only use this option with the SHA256 or SHA512 crypt
           method.

           By default, the number of rounds is defined by the
           SHA_CRYPT_MIN_ROUNDS and SHA_CRYPT_MAX_ROUNDS variables in
           /etc/login.defs.

AVVISI/CAVEAT

       The input file must be protected since it contains unencrypted
       passwords.

       PAM is not used to update the passwords. Only /etc/passwd and
       /etc/shadow are updated, and the various checks or options provided by
       PAM modules are not used.

CONFIGURATION

       The following configuration variables in /etc/login.defs change the
       behavior of this tool:

       ENCRYPT_METHOD (string)
           This defines the system default encryption algorithm for encrypting
           passwords (if no algorithm are specified on the command line).

           It can take one of these values:

           ·   DES (default)

           ·   MD5

           ·   SHA256

           ·   SHA512

               Note: this parameter overrides the MD5_CRYPT_ENAB variable.

               Note: if you use PAM, it is recommended to set this variable
               consistently with the PAM modules configuration.

       GID_MAX (number), GID_MIN (number)
           Range of group IDs used for the creation of regular groups by
           useradd, useradd, or newusers.

       MAX_MEMBERS_PER_GROUP (number)
           Maximum members per group entry. When the maximum is reached, a new
           group entry (line) is started in /etc/group (with the same name,
           same password, and same GID).

           The default value is 0, meaning that there are no limits in the
           number of members in a group.

           This feature (split group) permits to limit the length of lines in
           the group file. This is useful to make sure that lines for NIS
           groups are not larger than 1024 characters.

           If you need to enforce such limit, you can use 25.

           Note: split groups may not be supported by all tools (even in the
           Shadow toolsuite. You should not use this variable unless you
           really need it.

       MD5_CRYPT_ENAB (boolean)
           Indicate if passwords must be encrypted using the MD5-based
           algorithm. If set to yes, new passwords will be encrypted using the
           MD5-based algorithm compatible with the one used by recent releases
           of FreeBSD. It supports passwords of unlimited length and longer
           salt strings. Set to no if you need to copy encrypted passwords to
           other systems which don´t understand the new algorithm. Default is
           no.

           This variable is superceded by the ENCRYPT_METHOD variable or by
           any command line option used to configure the encryption algorithm.

           This variable is deprecated. You should use ENCRYPT_METHOD.

           Note: if you use PAM, it is recommended to set this variable
           consistently with the PAM modules configuration.

       PASS_MAX_DAYS (number)
           The maximum number of days a password may be used. If the password
           is older than this, a password change will be forced. If not
           specified, -1 will be assumed (which disables the restriction).

       PASS_MIN_DAYS (number)
           The minimum number of days allowed between password changes. Any
           password changes attempted sooner than this will be rejected. If
           not specified, -1 will be assumed (which disables the restriction).

       PASS_WARN_AGE (number)
           The number of days warning given before a password expires. A zero
           means warning is given only upon the day of expiration, a negative
           value means no warning is given. If not specified, no warning will
           be provided.

       SHA_CRYPT_MIN_ROUNDS (number), SHA_CRYPT_MAX_ROUNDS (number)
           When ENCRYPT_METHOD is set to SHA256 or SHA512, this defines the
           number of SHA rounds used by the encryption algorithm by default
           (when the number of rounds is not specified on the command line).

           With a lot of rounds, it is more difficult to brute forcing the
           password. But note also that more CPU resources will be needed to
           authenticate users.

           If not specified, the libc will choose the default number of rounds
           (5000).

           The values must be inside the 1000-999999999 range.

           If only one of the SHA_CRYPT_MIN_ROUNDS or SHA_CRYPT_MAX_ROUNDS
           values is set, then this value will be used.

           If SHA_CRYPT_MIN_ROUNDS > SHA_CRYPT_MAX_ROUNDS, the highest value
           will be used.

       SYS_GID_MAX (number), SYS_GID_MIN (number)
           Range of group IDs used for the creation of system groups by
           useradd, groupadd, or newusers.

       SYS_UID_MAX (number), SYS_UID_MIN (number)
           Range of user IDs used for the creation of system users by useradd
           or newusers.

       UID_MAX (number), UID_MIN (number)
           Range of user IDs used for the creation of regular users by useradd
           or newusers.

       UMASK (number)
           The permission mask is initialized to this value. If not specified,
           the permission mask will be initialized to 022.

FILE

       /etc/passwd
           informazioni sugli account utente.

       /etc/shadow
           Informazioni sicure sugli account di utenti.

       /etc/group
           Informazioni sugli account di gruppo.

       /etc/gshadow
           Informazioni sicure sugli account di gruppo.

       /etc/login.defs
           Shadow password suite configuration.

VEDERE ANCHE

       login.defs(5), passwd(1), useradd(8).