NEWUSERS(8) System Management Commands NEWUSERS(8)
NAME
newusers - update and create new users in batch
SYNOPSIS
newusers [options] [file]
DESCRIPTION
The newusers command reads a file (or the standard input by default)
and uses this information to update a set 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 exceptions explained below:
pw_name:pw_passwd:pw_uid:pw_gid:pw_gecos:pw_dir:pw_shell
pw_name
This is the name of the user.
It can be the name of a new user or the name of an existing user
(or a user created before by newusers). In case of an existing
user, the user's information will be changed, otherwise a new user
will be created.
pw_passwd
This field will be encrypted and used as the new value of the
encrypted password.
pw_uid
This field is used to define the UID of the user.
If the field is empty, a new (unused) UID will be defined
automatically by newusers.
If this field contains a number, this number will be used as the
UID.
If this field contains the name of an existing user (or the name of
a user created before by newusers), the UID of the specified user
will be used.
If the UID of an existing user is changed, the files ownership of
the user's file should be fixed manually.
pw_gid
This field is used to define the primary group ID for the user.
If this field contains the name of an existing group (or a group
created before by newusers), the GID of this group will be used as
the primary group ID for the user.
If this field is a number, this number will be used as the primary
group ID of the user. If no groups exist with this GID, a new group
will be created with this GID, and the name of the user.
If this field is empty, a new group will be created with the name
of the user and a GID will be automatically defined by newusers to
be used as the primary group ID for the user and as the GID for the
new group.
If this field contains the name of a group which does not exist
(and was not created before by newusers), a new group will be
created with the specified name and a GID will be automatically
defined by newusers to be used as the primary group ID for the user
and GID for the new group.
pw_gecos
This field is copied in the GECOS field of the user.
pw_dir
This field is used to define the home directory of the user.
If this field does not specify an existing directory, the specified
directory is created, with ownership set to the user being created
or updated and its primary group. Note that newusers does not
create parent directories of the new user's home directory. The
newusers command will fail to create the home directory if the
parent directories do not exist, and will send a message to stderr
informing the user of the failure. The newusers command will not
halt or return a failure to the calling shell if it fails to create
the home directory, it will continue to process the batch of new
users specified.
If the home directory of an existing user is changed, newusers does
not move or copy the content of the old directory to the new
location. This should be done manually.
pw_shell
This field defines the shell of the user. No checks are performed
on this field.
newusers first tries to create or change all the specified users, and
then write these changes to the user or group databases. If an error
occurs (except in the final writes to the databases), no changes are
committed to the databases.
This command is intended to be used in a large system environment where
many accounts are updated at a single time.
OPTIONS
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.
-h, --help
Display help message and exit.
-r, --system
Create a system account.
System users will be created with no aging information in
/etc/shadow, and their numeric identifiers are chosen 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).
-R, --root CHROOT_DIR
Apply changes in the CHROOT_DIR directory and use the configuration
files from the CHROOT_DIR directory.
-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.
CAVEATS
The input file must be protected since it contains unencrypted
passwords.
You should make sure the passwords and the encryption method respect
the system's password policy.
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.
GID_MAX (number), GID_MIN (number)
Range of group IDs used for the creation of regular groups by
useradd, groupadd, or newusers.
The default value for GID_MIN (resp. GID_MAX) is 1000 (resp.
60000).
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 superseded 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.
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 1000-999,999,999 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.
SUB_GID_MIN (number), SUB_GID_MAX (number), SUB_GID_COUNT (number)
If /etc/subuid exists, the commands useradd and newusers (unless
the user already have subordinate group IDs) allocate SUB_GID_COUNT
unused group IDs from the range SUB_GID_MIN to SUB_GID_MAX for each
new user.
The default values for SUB_GID_MIN, SUB_GID_MAX, SUB_GID_COUNT are
respectively 100000, 600100000 and 65536.
SUB_UID_MIN (number), SUB_UID_MAX (number), SUB_UID_COUNT (number)
If /etc/subuid exists, the commands useradd and newusers (unless
the user already have subordinate user IDs) allocate SUB_UID_COUNT
unused user IDs from the range SUB_UID_MIN to SUB_UID_MAX for each
new user.
The default values for SUB_UID_MIN, SUB_UID_MAX, SUB_UID_COUNT are
respectively 100000, 600100000 and 65536.
SYS_GID_MAX (number), SYS_GID_MIN (number)
Range of group IDs used for the creation of system groups by
useradd, groupadd, or newusers.
The default value for SYS_GID_MIN (resp. SYS_GID_MAX) is 101
(resp. GID_MIN-1).
SYS_UID_MAX (number), SYS_UID_MIN (number)
Range of user IDs used for the creation of system users by useradd
or newusers.
The default value for SYS_UID_MIN (resp. SYS_UID_MAX) is 101
(resp. UID_MIN-1).
UID_MAX (number), UID_MIN (number)
Range of user IDs used for the creation of regular users by useradd
or newusers.
The default value for UID_MIN (resp. UID_MAX) is 1000 (resp.
60000).
UMASK (number)
The file mode creation mask is initialized to this value. If not
specified, the mask will be initialized to 022.
useradd and newusers use this mask to set the mode of the home
directory they create
It is also used by login to define users' initial umask. Note that
this mask can be overridden by the user's GECOS line (if
QUOTAS_ENAB is set) or by the specification of a limit with the K
identifier in limits(5).
FILES
/etc/passwd
User account information.
/etc/shadow
Secure user account information.
/etc/group
Group account information.
/etc/gshadow
Secure group account information.
/etc/login.defs
Shadow password suite configuration.
/etc/subgid
Per user subordinate group IDs.
/etc/subuid
Per user subordinate user IDs.
SEE ALSO
login.defs(5), passwd(1), subgid(5), subuid(5),useradd(8).
shadow-utils 4.6 08/09/2019 NEWUSERS(8)
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