Directory Services 7.4.3

About password policies

DS password policies govern passwords, account lockout, and account status notification.

DS servers support per-server password policies stored in the configuration, and subentry password policies stored in the (replicated) directory data:

Type Notes

Per-server password policies

  • Use for default policies, and policies for top-level administrative accounts.

  • You must manually apply policy updates to each replica server configuration.

  • Updates require write access to the server configuration.

DS subentry password policies

  • Use for all user accounts stored in application data.

  • Replication applies each policy update to all replicas.

  • Updates require the subentry-write privilege, and ACIs to write the policy.
Per-server policies are not replicated; subentry policies are.
Figure 1. Per-Server and subentry password policies

Per-server password policies

You manage per-server password policies with the dsconfig command. When changing a per-server policy, you must update each replica in your deployment.

By default, there are two per-server password policies:

  • The Default Password Policy for users.

  • The Root Password Policy for the directory superuser, uid=admin.

The following example displays the default per-server password policy for users:

$ dsconfig \
 get-password-policy-prop \
 --hostname localhost \
 --port 4444 \
 --bindDN uid=admin \
 --bindPassword password \
 --policy-name "Default Password Policy" \
 --advanced \
 --usePkcs12TrustStore /path/to/opendj/config/keystore \
 --trustStorePassword:file /path/to/opendj/config/keystore.pin \
 --no-prompt

Property                                  : Value(s)
------------------------------------------:------------------------------------
account-status-notification-handler       : -
allow-expired-password-changes            : false
allow-multiple-password-values            : false
allow-pre-encoded-passwords               : false
allow-user-password-changes               : true
default-password-storage-scheme           : PBKDF2-HMAC-SHA256
deprecated-password-storage-scheme        : -
expire-passwords-without-warning          : false
force-change-on-add                       : false
force-change-on-reset                     : false
grace-login-count                         : 0
idle-lockout-interval                     : 0 s
java-class                                : org.opends.server.core.PasswordPoli
                                          : cyFactory
last-login-time-attribute                 : -
last-login-time-format                    : -
lockout-duration                          : 0 s
lockout-failure-count                     : 0
lockout-failure-expiration-interval       : 0 s
max-password-age                          : 0 s
max-password-reset-age                    : 0 s
min-password-age                          : 0 s
password-attribute                        : userPassword
password-change-requires-current-password : false
password-expiration-warning-interval      : 5 d
password-generator                        : Random Password Generator
password-history-count                    : 0
password-history-duration                 : 0 s
password-validator                        : At least 8 characters, Common
                                          : passwords
previous-last-login-time-format           : -
require-change-by-time                    : -
require-secure-authentication             : true
require-secure-password-changes           : true
skip-validation-for-administrators        : false
state-update-failure-policy               : reactive

For detailed descriptions of each property, refer to Password Policy.

These settings are configured by default:

  • When granted access, users can change their passwords.

  • DS servers use the standard userPassword attribute to store passwords.

    DS servers also support the alternative standard authPassword attribute.

  • When you import LDIF with userPassword values, DS servers apply a one-way hash to the passwords before storing them.

    When a user provides a password value during a bind, for example, the server hashes the incoming password, and compares it with the stored value. This mechanism helps prevent even the directory superuser from recovering the plain text password:

    $ ldapsearch \
 --hostname localhost \
 --port 1636 \
 --useSsl \
 --usePkcs12TrustStore /path/to/opendj/config/keystore \
 --trustStorePassword:file /path/to/opendj/config/keystore.pin \
 --bindDN uid=admin \
 --bindPassword password \
 --baseDN dc=example,dc=com \
 "(uid=bjensen)" \
 userpassword

dn: uid=bjensen,ou=People,dc=example,dc=com
userpassword: {PBKDF2-HMAC-SHA256}10:<hash>

  • The server can set a random password when a password administrator resets a user’s password.

Many capabilities are not set by default:

  • No lockout.

  • No password expiration.

  • No password validator to check that passwords contain the appropriate mix of characters.

If the directory service enforces password policy, configure at least the default password policy accordingly.

DS subentry password policies

You manage password policies as LDAP subentries in the application data. Replication applies updates to subentry password policies to all other replicas. Password policy administrators do not need access to the server configuration.

The DS subentry password policy entries have the object classes:

  • ds-pwp-password-policy for most password policy features.

  • A set of password validator object classes for specific validators that derive from the abstract ds-pwp-validator class for password validation configuration.

  • ds-pwp-random-generator for password generation on reset.

The following tables describe password policy attributes per object class:

Core policy attributes

Object class: ds-pwp-password-policy

Attribute Description

ds-pwp-password-attribute (required)

The attribute type used to hold user passwords.

ds-pwp-default-password-storage-scheme (required)

Names of enabled password storage schemes used to encode plaintext passwords.

Default: PBKDF2-HMAC-SHA256.

cn

Name of the password policy

ds-pwp-allow-user-password-changes

Whether users can change their passwords, assuming access control allows it.

Default: true.

ds-pwp-account-status-notification-handler

Names of enabled account status notification handlers to use with this policy.

Use the dsconfig list-account-status-notification-handlers command. The first column of the output shows the names. The third column shows whether the handler is enabled.

ds-pwp-allow-expired-password-changes

Whether the user can change an expired password with the password modify extended operation.

Default: false.

ds-pwp-allow-multiple-password-values

Whether user entries can have multiple distinct passwords. Any password is sufficient to authenticate.

Default: false.

ds-pwp-allow-pre-encoded-passwords

Whether users can change their passwords by providing a pre-encoded value.

Default: false.

ds-pwp-deprecated-password-storage-scheme

Names of deprecated password storage schemes for this policy.

On successful authentication, encode the password with the default.

ds-pwp-expire-passwords-without-warning

Whether to allow a user’s password to expire even if that user has never received an expiration warning notification.

Default: false.

ds-pwp-force-change-on-add

Whether users are forced to change their passwords upon first authentication after their accounts are added.

Use the ds-pwp-max-password-reset-age property to control how long users have to change their passwords.

Default: false.

ds-pwp-force-change-on-reset

Whether users are forced to change their passwords after password reset by an administrator. For this purpose, anyone with permission to change a given user’s password other than that user is an administrator.

Use the ds-pwp-max-password-reset-age property to control how long users have to change their passwords.

Default: false.

ds-pwp-grace-login-count

Number of grace logins that a user is allowed after the account has expired so the user can update their password.

Default: 0 (disabled).

ds-pwp-idle-lockout-interval

Maximum number of seconds that an account may remain idle (the associated user does not authenticate to the server) before that user is locked out. Requires maintaining a last login time attribute.

Default: 0 seconds (inactive).

ds-pwp-last-login-time-attribute

Name or OID of the attribute type that is used to hold the last login time for users.

Default: The last-login-time-attribute setting from the default password policy. By default, last-login-time-attribute is not set.

ds-pwp-last-login-time-format

Format string that is used to generate the last login time value for users.

The format string must match the syntax of the ds-pwp-last-login-time-attribute attribute, and must be a valid format string for the java.text.SimpleDateFormat class.

Default: yyyyMMddHHmmss’Z'.

ds-pwp-lockout-duration

Duration that an account is locked after too many authentication failures.

Default: 0 seconds (account remains locked until the administrator resets the password).

ds-pwp-lockout-failure-count

Maximum number of authentication failures that a user is allowed before the account is locked out.

Default: 0 (disabled).

ds-pwp-lockout-failure-expiration-interval

Duration before an authentication failure is no longer counted against a user for the purposes of account lockout.

Default: 0 seconds (never expire).

ds-pwp-max-password-age

Duration that a user can continue using the same password before it must be changed (the password expiration interval).

Default: 0 seconds (passwords never expire).

ds-pwp-max-password-reset-age

Maximum number of seconds that users have to change passwords after they have been reset by an administrator before they become locked.

Users are only required to change their password after it is reset if ds-pwp-force-change-on-add or ds-pwp-force-change-on-reset is true.

Default: 0 seconds.

ds-pwp-min-password-age

Minimum duration after a password change before the user is allowed to change the password again.

Default: 0 seconds.

ds-pwp-password-change-requires-current-password

Whether user password changes must include the user’s current password before the change is allowed. This can be done with either the password modify extended operation, or a modify operation using delete and add.

Default: false.

ds-pwp-password-expiration-warning-interval

Duration before a user’s password actually expires that the server begins to include warning notifications in bind responses for that user.

Default: 5 days.

ds-pwp-password-history-count

Maximum number of former passwords to maintain in the password history.

A value of zero indicates that either no password history is to be maintained if the password history duration has a value of zero seconds, or that there is no maximum number of passwords to maintain in the history if the password history duration has a value greater than zero seconds.

Default: 0.

When modifying a password, DS checks the new password against each hashed password value in the entry.

If the password policy specifies a computationally intensive password storage scheme, such as Argon2, Bcrypt, PKCS5S2, or a PBKDF2-based scheme, enabling password history multiplies the cost of changing the password.

DS must calculate the computationally intensive hash from the new password separately for each comparison with a hashed password in the password history. As a result, if it takes 100 ms to calculate the hash for a new password, and the applicable password policy has a password history count of 7, the calculations to modify the password can take up to 700 ms.

ds-pwp-password-history-duration

Maximum number of seconds that passwords remain in the password history.

Default: 0 seconds (inactive).

ds-pwp-previous-last-login-time-format

Format string(s) that might have been used with the last login time at any point in the past for users associated with the password policy.

Default: yyyyMMddHHmmss’Z'.

ds-pwp-require-change-by-time

Time by which all users with the associated password policy must change their passwords. Specified in generalized time form.

ds-pwp-require-secure-authentication

Whether users with the associated password policy are required to authenticate in a secure manner.

Default: false.

ds-pwp-require-secure-password-changes

Whether users with the associated password policy are required to change their password in a secure manner that does not expose the credentials.

Default: false.

ds-pwp-skip-validation-for-administrators

Whether passwords set by administrators are allowed to bypass the password validation process.

Default: false.

ds-pwp-state-update-failure-policy

How the server deals with the inability to update password policy state information during an authentication attempt.

One of the following:

  • ignore: If a bind attempt would otherwise be successful, then do not reject it if a problem occurs while attempting to update the password policy state information for the user.

  • proactive: Proactively reject any bind attempt if it is known ahead of time that it would not be possible to update the user’s password policy state information.

  • reactive (default): Even if a bind attempt would otherwise be successful, reject it if a problem occurs while attempting to update the password policy state information for the user.

Value validator attributes

Object class: ds-pwp-attribute-value-validator

Attribute Description

ds-pwp-attribute-value-test-reversed-password

Whether this password validator should test the reversed value of the provided password as well as the order in which it was given.

Default: false.

ds-pwp-attribute-value-match-attribute

Name(s) of the attribute(s) whose values should be checked to determine whether they match the provided password.

If no values are provided, then the server checks if the proposed password matches the value of any user attribute in the user’s entry. The server does not check values of operational attributes.

ds-pwp-attribute-value-check-substrings

Whether this password validator is to match portions of the password string against attribute values and portions of attribute values against the password string.

When false, the server checks whether the entire password matches any user attribute values. When true, the server checks whether the password contains portions of attribute values and whether the attribute values contain portions of the password.

Consider the case of Babs Jensen (uid: bjensen) changing her password. The following table describes the effects of the settings:

Setting New Password Password Modification Result

ds-pwp-attribute-value-check-substrings: false

bjense

Success

ds-pwp-attribute-value-check-substrings: false

bjensen

Failure: 19 (Constraint Violation)

ds-pwp-attribute-value-check-substrings: false

bjensens

Success

ds-pwp-attribute-value-check-substrings: true

bjense

Failure: 19 (Constraint Violation)

ds-pwp-attribute-value-check-substrings: true

bjensen

Failure: 19 (Constraint Violation)

ds-pwp-attribute-value-check-substrings: true

bjensens

Failure: 19 (Constraint Violation)

In summary:

  • bjense is allowed when the setting is false because the password does not exactly match and rejected when the setting is true because Babs’s user ID contains the password.

  • bjensen is rejected in both cases because the password exactly matches and contains Babs’s user ID.

  • bjensens is allowed when the setting is false because the password does not exactly match and rejected when the setting is true because the password contains Babs’s user ID.

Default: false.

ds-pwp-attribute-value-min-substring-length

The minimal length of the substring within the password when substring checking is enabled.

Default: 0.

Character set attributes

Object class: ds-pwp-character-set-validator

Attribute Description

ds-pwp-character-set-allow-unclassified-characters

Whether this password validator allows passwords to contain characters outside of any of the user-defined character sets and ranges.

Default: false.

ds-pwp-character-set-min-character-sets

Minimum number of character sets and ranges that a password must contain.

Use in conjunction with optional character sets and ranges (those requiring zero characters). The value must include any mandatory character sets and ranges (those requiring greater than zero characters). This is useful in situations where a password must contain characters from mandatory character sets and ranges, and characters from at least N optional character sets and ranges. For example, it is quite common to require that a password contains at least one non-alphanumeric character as well as characters from two alphanumeric character sets (lower-case, upper-case, digits). In this case, this property should be set to 3.

ds-pwp-character-set-character-set

A character set containing characters that a password may contain, and a value indicating the minimum number of characters required from that set.

Each value must be an integer (indicating the minimum required characters from the set which may be zero, indicating that the character set is optional) followed by a colon and the characters to include in that set. For example, 3:abcdefghijklmnopqrstuvwxyz indicates that a user password must contain at least three characters from the set of lowercase ASCII letters.

Multiple character sets can be defined in separate values, although no character can appear in more than one character set.

ds-pwp-character-set-character-set-ranges

A character range containing characters that a password may contain, and a value indicating the minimum number of characters required from that range. Each value must be an integer (indicating the minimum required characters from the range which may be zero, indicating that the character range is optional) followed by a colon and one or more range specifications.

A range specification is 3 characters: the first character allowed, a minus, and the last character allowed. For example, 3:A-Za-z0-9. The ranges in each value should not overlap, and the characters in each range specification should be ordered.

Dictionary attributes

Object class: ds-pwp-dictionary-validator

Attribute Description

ds-pwp-dictionary-data (required)

A gzipped password dictionary, one word per line.

This is a single-valued attribute.

ds-pwp-dictionary-case-sensitive-validation

Whether this password validator should treat password characters in a case-sensitive manner.

Default: false.

ds-pwp-dictionary-check-substrings

Whether this password validator is to match portions of the password string against dictionary words.

Default: false (match only the entire password against dictionary words).

ds-pwp-dictionary-min-substring-length

The minimal length of the substring within the password in case substring checking is enabled.

Default: 0.

ds-pwp-dictionary-test-reversed-password

Whether this password validator should test the reversed value of the provided password as well as the order in which it was given.

Default: false.

Password length attributes

Object class: ds-pwp-length-based-validator

Attribute Description

ds-pwp-length-based-max-password-length

Minimum plaintext password length.

Default: 0 (undefined).

ds-pwp-length-based-min-password-length

Minimum plaintext password length.

Default: 6.

Repeated characters attributes

Object class: ds-pwp-repeated-characters-validator

Attribute Description

ds-pwp-repeated-characters-max-consecutive-length

The maximum number of times that any character can appear consecutively in a password value.

Default: 0 (no maximum limit is enforced).

ds-pwp-repeated-characters-case-sensitive-validation

Whether this password validator should treat password characters in a case-sensitive manner.

Default: false.

Similarity attributes

Object class: ds-pwp-similarity-based-validator

Attribute Description

ds-pwp-similarity-based-min-password-difference

The minimum difference the new and old password.

The implementation uses the Levenshtein Distance algorithm to determine the minimum number of changes (where a change may be inserting, deleting, or replacing a character) to transform one string into the other. It can prevent users from making only minor changes to their current password when setting a new password. Note that for this password validator to be effective, it must have access to the user’s current password. Therefore, if this password validator is to be enabled, also set ds-pwp-password-change-requires-current-password: true.

Default: 0 (no difference between passwords is acceptable).

Unique characters attributes

Object class: ds-pwp-unique-characters-validator

Attribute Description

ds-pwp-unique-characters-case-sensitive-validation

Whether this password validator should treat password characters in a case-sensitive manner.

Default: false.

ds-pwp-unique-characters-min-unique-characters

The minimum number of unique characters that a password will be allowed to contain.

Default: 0 (no minimum value is enforced).

Generator attributes

Object class: ds-pwp-random-generator

Attribute Description

ds-pwp-random-password-character-set (required)

Named character sets. The format of the character set is the name of the set followed by a colon and the characters that are in that set. For example, the value alpha:abcdefghijklmnopqrstuvwxyz defines a character set named alpha containing all of the lower-case ASCII alphabetic characters.

ds-pwp-random-password-format (required)

The format to use for the generated password. The value is a comma-delimited list of elements in which each of those elements is comprised of the name of a character set defined in the password-character-set property, a colon, and the number of characters to include from that set. For example, a value of alpha:3,numeric:2,alpha:3 generates an 8-character password in which the first three characters are from the alpha set, the next two are from the numeric set, and the final three are from the alpha set.

Interoperable password policies

DS servers support the Internet-Draft, Password Policy for LDAP Directories (version 09). The password policies are expressed as LDAP subentries with objectClass: pwdPolicy. An Internet-Draft password policy effectively overrides settings in the default per-server password policy for users, inheriting settings that it does not support or does not include from the per-server password policy.

The following table describes Internet-Draft policy attributes:

Internet-Draft attributes

Object class: pwdPolicy

Attribute Description

pwdAttribute (required)

The attribute type used to hold user passwords.

pwdAllowUserChange

Whether users can change their passwords.

Default: true.

pwdExpireWarning

Maximum number of seconds before a user’s password actually expires that the server begins to include warning notifications in bind responses for that user.

Default: 432000 seconds.

pwdFailureCountInterval

Length of time before an authentication failure is no longer counted against a user for the purposes of account lockout.

Default: 0 seconds (never expire).

pwdGraceAuthNLimit

Number of grace logins that a user is allowed after the account has expired so the user can update their password.

Default: 0 (disabled).

pwdInHistory

Maximum number of former passwords to maintain in the password history.

Default: 0 (disabled).

pwdLockoutDuration

Number of seconds that an account is locked after too many authentication failures.

Default: 0 seconds (account remains locked indefinitely).

pwdMaxAge

Maximum number of seconds that a user can continue using the same password before it must be changed (the password expiration interval).

Default: 0 seconds (disabled).

pwdMaxFailure

Maximum number of authentication failures that a user is allowed before the account is locked out.

Default: 0.

pwdMinAge

Minimum number of seconds after a password change before the user is allowed to change the password again.

Default: 0 seconds (disabled).

pwdMustChange

Whether users are forced to change their passwords after password reset by an administrator.

Default: false.

pwdSafeModify

Whether user password changes must use the password modify extended operation, and must include the user’s current password before the change is allowed.

Default: false.

Overrides

The following table lists Internet-Draft policy attributes that override the per-server policy properties:

Internet-Draft policy attribute Overrides this server policy property

pwdAllowUserChange

allow-user-password-changes

pwdMustChange

force-change-on-reset

pwdGraceAuthNLimit

grace-login-count

pwdLockoutDuration

lockout-duration

pwdMaxFailure

lockout-failure-count

pwdFailureCountInterval

lockout-failure-expiration-interval

pwdMaxAge

max-password-age

pwdMinAge

min-password-age

pwdAttribute

password-attribute

pwdSafeModify

password-change-requires-current-password

pwdExpireWarning

password-expiration-warning-interval

pwdInHistory

password-history-count

Ignored attributes

DS servers ignore the following Internet-Draft password policy attributes:

  • pwdCheckQuality, because DS servers have password validators.

  • pwdMinLength, because you can use a length-based password validator instead.

  • pwdLockout, because DS servers use other lockout-related password policy attributes.

Inheritance

Internet-Draft based password policies inherit these settings from the default per-server policy for users:

  • account-status-notification-handlers

  • allow-expired-password-changes

  • allow-multiple-password-values

  • allow-pre-encoded-passwords

  • default-password-storage-schemes

  • deprecated-password-storage-schemes

  • expire-passwords-without-warning

  • force-change-on-add

  • idle-lockout-interval

  • last-login-time-attribute

  • last-login-time-format

  • max-password-reset-age

  • password-generator

  • password-history-duration

  • password-validators

  • previous-last-login-time-formats

  • require-change-by-time

  • require-secure-authentication

  • require-secure-password-changes

  • skip-validation-for-administrators

  • state-update-failure-policy