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passwd(1)

Name | Synopsis | Description | Options | Operands | Environment Variables | Exit Status | Files | Attributes | See Also | Notes

Name

passwd– change login password and password attributes

Synopsis

passwd  [-r files |  -r ldap |  -r nis |  -r nisplus]
 [name]

passwd  [-r files] [-egh] [name]

passwd  [-r files] -s [-a]

passwd  [-r files] -s [name]

passwd  [-r files] [-d |  -l |  -u |  -N] [-f] [-n min]
 [-w warn] [-x max] name

passwd   -r ldap [-egh] [name]

passwd [-r ldap ] -s [-a]

passwd [-r ldap ] -s [name]

passwd -r ldap [-d | -l | -u | -N] [-f] [-n min] [-w warn] [-x max] name

passwd   -r nis [-egh] [name]

passwd   -r nisplus [-egh] [-D domainname] [name]

passwd   -r nisplus -s [-a]

passwd   -r nisplus [-D domainname] -s [name]

passwd   -r nisplus [-l |  -u |  -N] [-f] [-n min] [-w warn]
 [-x max] [-D domainname] name

Description

The passwd command changes the password or lists password attributes associated with the user's login name. Additionally, privileged users can use passwd to install or change passwords and attributes associated with any login name.

When used to change a password, passwd prompts everyone for their old password, if any. It then prompts for the new password twice. When the old password is entered, passwd checks to see if it has aged sufficiently. If aging is insufficient, passwd terminates; see pwconv(1M), nistbladm(1), and shadow(4) for additional information.

The pwconv command creates and updates /etc/shadow with information from /etc/passwd. pwconv relies on a special value of 'x' in the password field of /etc/passwd. This value of 'x' indicates that the password for the user is already in /etc/shadow and should not be modified.

If aging is sufficient, a check is made to ensure that the new password meets construction requirements. When the new password is entered a second time, the two copies of the new password are compared. If the two copies are not identical, the cycle of prompting for the new password is repeated for, at most, two more times.

Passwords must be constructed to meet the following requirements:

• Each password must have PASSLENGTH characters, where PASSLENGTH is defined in /etc/default/passwd and is set to 6. Setting PASSLENGTH to more than eight characters requires configuring policy.conf(4) with an algorithm that supports greater than eight characters.

• Each password must meet the configured complexity constraints specified in /etc/default/passwd.

• Each password must not be a member of the configured dictionary as specified in /etc/default/passwd.

• For accounts in name services which support password history checking, if prior password history is defined, new passwords must not be contained in the prior password history.

If all requirements are met, by default, the passwd command consults /etc/nsswitch.conf to determine in which repositories to perform password update. It searches the passwd and passwd_compat entries. The sources (repositories) associated with these entries are updated. However, the password update configurations supported are limited to the following cases. Failure to comply with the configurations prevents users from logging onto the system. The password update configurations are:

• passwd: files

• passwd: files ldap

• passwd: files nis

• passwd: files nisplus

• passwd: compat (==> files nis)

• passwd: compat (==> files ldap)

  passwd_compat: ldap

• passwd: compat (==> files nisplus)

  passwd_compat: nisplus

Network administrators, who own the NIS+ password table, can change any password attributes. The administrator configured for updating LDAP shadow information can also change any password attributes. See ldapclient(1M).

When a user has a password stored in one of the name services as well as a local files entry, the passwd command updates both. It is possible to have different passwords in the name service and local files entry. Use passwd -r to change a specific password repository.

In the files case, superusers (for instance, real and effective uid equal to 0, see id(1M) and su(1M)) can change any password. Hence, passwd does not prompt privileged users for the old password. Privileged users are not forced to comply with password aging and password construction requirements. A privileged user can create a null password by entering a carriage return in response to the prompt for a new password. (This differs from passwd -d because the password prompt is still displayed.) If NIS is in effect, superuser on the root master can change any password without being prompted for the old NIS passwd, and is not forced to comply with password construction requirements.

If LDAP is in effect, superuser on any Native LDAP client system can change any password without being prompted for the old LDAP password, and is not forced to comply with password construction requirements.

Normally, passwd entered with no arguments changes the password of the current user. When a user logs in and then invokes su(1M) to become superuser or another user, passwd changes the original user's password, not the password of the superuser or the new user.

Any user can use the -s option to show password attributes for his or her own login name, provided they are using the -r nisplus argument. Otherwise, the -s argument is restricted to the superuser.

The format of the display is:

name status mm/dd/yy min max warn

or, if password aging information is not present,

name status

where

name

The login ID of the user.

status

The password status of name.

The status field can take the following values:

PS

This account has a password.

NL

This account is a no login account. See Security.

LK

This account is locked account. See Security.

NP

This account has no password and is therefore open without authentication.

mm/dd/yy

The date password was last changed for name. All password aging dates are determined using Greenwich Mean Time (Universal Time) and therefore can differ by as much as a day in other time zones.

min

The minimum number of days required between password changes for name. MINWEEKS is found in /etc/default/passwd and is set to NULL.

max

The maximum number of days the password is valid for name. MAXWEEKS is found in /etc/default/passwd and is set to NULL.

warn

The number of days relative to max before the password expires and the name are warned.

Security

passwd uses pam(3PAM) for password change. It calls PAM with a service name passwd and uses service module type auth for authentication and password for password change.

Locking an account (-l option) does not allow its use for password based login or delayed execution (such as at(1), batch(1), or cron(1M)). The -N option can be used to disallow password based login, while continuing to allow delayed execution.

Options

The following options are supported:

-a

Shows password attributes for all entries. Use only with the -s option. name must not be provided. For the nisplus repository, this shows only the entries in the NIS+ password table in the local domain that the invoker is authorized to read. For the files and ldap repository, this is restricted to the superuser.

-D domainname

Consults the passwd.org_dir table in domainname. If this option is not specified, the default domainname returned by nis_local_directory(3NSL) are used. This domain name is the same as that returned by domainname(1M).

-e

Changes the login shell. For the files repository, this only works for the superuser. Normal users can change the ldap, nis, or nisplus repositories. The choice of shell is limited by the requirements of getusershell(3C). If the user currently has a shell that is not allowed by getusershell, only root can change it.

-g

Changes the gecos (finger) information. For the files repository, this only works for the superuser. Normal users can change the ldap, nis, or nisplus repositories.

-h

Changes the home directory.

-r

Specifies the repository to which an operation is applied. The supported repositories are files, ldap, nis, or nisplus.

-s name

Shows password attributes for the login name. For the nisplus repository, this works for everyone. However for the files repository, this only works for the superuser. It does not work at all for the nis and ldap repository which does not support password aging.

Privileged User Options

Only a privileged user can use the following options:

-d

Deletes password for name and unlocks the account. The login name is not prompted for password. It is only applicable to the files and ldap repository.

-f

Forces the user to change password at the next login by expiring the password for name.

-l

Locks password entry for name. See the -d or -u option for unlocking the account.

-N

Makes the password entry for name a value that cannot be used for login, but does not lock the account. See the -d option for removing the value, or to set a password to allow logins.

-n min

Sets minimum field for name. The min field contains the minimum number of days between password changes for name. If min is greater than max, the user can not change the password. Always use this option with the -x option, unless max is set to -1 (aging turned off). In that case, min need not be set.

-u

Unlocks a locked password for entry name. See the -d option for removing the locked password, or to set a password to allow logins.

-w warn

Sets warn field for name. The warn field contains the number of days before the password expires and the user is warned. This option is not valid if password aging is disabled.

-x max

Sets maximum field for name. The max field contains the number of days that the password is valid for name. The aging for name is turned off immediately if max is set to -1.

Operands

The following operand is supported:

name

User login name.

Environment Variables

If any of the LC_* variables, that is, LC_CTYPE, LC_MESSAGES, LC_TIME, LC_COLLATE, LC_NUMERIC, and LC_MONETARY (see environ(5)), are not set in the environment, the operational behavior of passwd for each corresponding locale category is determined by the value of the LANG environment variable. If LC_ALL is set, its contents are used to override both the LANG and the other LC_* variables. If none of the above variables is set in the environment, the C (U.S. style) locale determines how passwd behaves.

LC_CTYPE

Determines how passwd handles characters. When LC_CTYPE is set to a valid value, passwd can display and handle text and filenames containing valid characters for that locale. passwd can display and handle Extended Unix Code (EUC) characters where any individual character can be 1, 2, or 3 bytes wide. passwd can also handle EUC characters of 1, 2, or more column widths. In the C locale, only characters from ISO 8859-1 are valid.

LC_MESSAGES

Determines how diagnostic and informative messages are presented. This includes the language and style of the messages, and the correct form of affirmative and negative responses. In the C locale, the messages are presented in the default form found in the program itself (in most cases, U.S. English).

Exit Status

The passwd command exits with one of the following values:

0

Success.

1

Permission denied.

2

Invalid combination of options.

3

Unexpected failure. Password file unchanged.

4

Unexpected failure. Password file(s) missing.

5

Password file(s) busy. Try again later.

6

Invalid argument to option.

7

Aging option is disabled.

8

No memory.

9

System error.

10

Account expired.

Files

/etc/default/passwd

Default values can be set for the following flags in /etc/default/passwd. For example: MAXWEEKS=26

DICTIONDBDIR

The directory where the generated dictionary databases reside. Defaults to /var/passwd.

If neither DICTIONLIST nor DICTIONDBDIR is specified, the system does not perform a dictionary check.

DICTIONLIST

DICTIONLIST can contain list of comma separated dictionary files such as DICTIONLIST=file1, file2, file3. Each dictionary file contains multiple lines and each line consists of a word and a NEWLINE character (similar to /usr/share/lib/dict/words.) You must specify full pathnames. The words from these files are merged into a database that is used to determine whether a password is based on a dictionary word.

If neither DICTIONLIST nor DICTIONDBDIR is specified, the system does not perform a dictionary check.

To pre-build the dictionary database, see mkpwdict(1M).

HISTORY

Maximum number of prior password history to keep for a user. Setting the HISTORY value to zero (0), or removing the flag, causes the prior password history of all users to be discarded at the next password change by any user. The default is not to define the HISTORY flag. The maximum value is 26. Currently, this functionality is enforced only for user accounts defined in the files name service (local passwd(4)/shadow(4)).

MAXREPEATS

Maximum number of allowable consecutive repeating characters. If MAXREPEATS is not set or is zero (0), the default is no checks

MAXWEEKS

Maximum time period that password is valid.

MINALPHA

Minimum number of alpha character required. If MINALPHA is not set, the default is 2.

MINDIFF

Minimum differences required between an old and a new password. If MINDIFF is not set, the default is 3.

MINDIGIT

Minimum number of digits required. If MINDIGIT is not set or is set to zero (0), the default is no checks. You cannot be specify MINDIGIT if MINNONALPHA is also specified.

MINLOWER

Minimum number of lower case letters required. If not set or zero (0), the default is no checks.

MINNONALPHA

Minimum number of non-alpha (including numeric and special) required. If MINNONALPHA is not set, the default is 1. You cannot specify MINNONALPHA if MINDIGIT or MINSPECIAL is also specified.

MINWEEKS

Minimum time period before the password can be changed.

MINSPECIAL

Minimum number of special (non-alpha and non-digit) characters required. If MINSPECIAL is not set or is zero (0), the default is no checks. You cannot specify MINSPECIAL if you also specify MINNONALPHA.

MINUPPER

Minimum number of upper case letters required. If MINUPPER is not set or is zero (0), the default is no checks.

NAMECHECK

Enable/disable checking or the login name. The default is to do login name checking. A case insensitive value of no disables this feature.

PASSLENGTH

Minimum length of password, in characters.

WARNWEEKS

Time period until warning of date of password's ensuing expiration.

WHITESPACE

Determine if white space characters are allowed in passwords. Valid values are YES and NO. If WHITESPACE is not set or is set to YES, white space characters are allowed.

/etc/oshadow

Temporary file used by passwd, passmgmt and pwconv to update the real shadow file.

/etc/passwd

Password file.

/etc/shadow

Shadow password file.

/etc/shells

Shell database.

Attributes

See attributes(5) for descriptions of the following attributes:

ATTRIBUTE TYPE	ATTRIBUTE VALUE
Availability	SUNWcsu
CSI	Enabled
Interface Stability	See below.

The human readable output is Unstable. The options are Evolving.

See Also

at(1), batch(1), finger(1), login(1), nistbladm(1), cron(1M), domainname(1M), eeprom(1M), id(1M), mkpwdict(1M), passmgmt(1M), pwconv(1M), su(1M), useradd(1M), userdel(1M), usermod(1M), crypt(3C), getpwnam(3C), getspnam(3C), getusershell(3C), nis_local_directory(3NSL), pam(3PAM), loginlog(4), nsswitch.conf(4), pam.conf(4), passwd(4), policy.conf(4), shadow(4), shells(4), attributes(5), environ(5), pam_authtok_check(5), pam_authtok_get(5), pam_authtok_store(5), pam_dhkeys(5), pam_ldap(5), pam_unix_account(5), pam_unix_auth(5), pam_unix_session(5)

Notes

The pam_unix(5) module is no longer supported. Similar functionality is provided by pam_unix_account(5), pam_unix_auth(5), pam_unix_session(5), pam_authtok_check(5), pam_authtok_get(5), pam_authtok_store(5), pam_dhkeys(5), and pam_passwd_auth(5).

The nispasswd and ypasswd commands are wrappers around passwd. Use of nispasswd and ypasswd is discouraged. Use passwd -r repository_name instead.

NIS+ might not be supported in future releases of the Solaris operating system. Tools to aid the migration from NIS+ to LDAP are available in the current Solaris release. For more information, visit http://www.sun.com/directory/nisplus/transition.html.

Changing a password in the files and ldap repositories clear the failed login count.

Changing a password reactivates an account deactivated for inactivity for the length of the inactivity period.

Input terminal processing might interpret some key sequences and not pass them to the passwd command.

Name | Synopsis | Description | Options | Operands | Environment Variables | Exit Status | Files | Attributes | See Also | Notes