pwquality.conf - configuration for the libpwquality library
/etc/security/pwquality.conf /etc/security/pwquality.conf.d/*.conf
pwquality.conf provides a way to configure the default password quality requirements for the system passwords. This file is read by the libpwquality library and utilities that use this library for checking and generating passwords. The file has a very simple name = value format with possible comments starting with "#" character. The whitespace at the beginning of line, end of line, and around the "=" sign is ignored. The libpwquality library also first reads all *.conf files from the /etc/security/pwquality.conf.d directory in ASCII sorted order. The values of the same settings are overriden in the order the files are parsed.
The possible options in the file are: difok Number of characters in the new password that must not be present in the old password. (default 1) minlen Minimum acceptable size for the new password (plus one if credits are not disabled which is the default). (See pam_pwquality(8).) Cannot be set to lower value than 6. (default 8) dcredit The maximum credit for having digits in the new password. If less than 0 it is the minimum number of digits in the new password. (default 0) ucredit The maximum credit for having uppercase characters in the new password. If less than 0 it is the minimum number of uppercase characters in the new password. (default 0) lcredit The maximum credit for having lowercase characters in the new password. If less than 0 it is the minimum number of lowercase characters in the new password. (default 0) ocredit The maximum credit for having other characters in the new password. If less than 0 it is the minimum number of other characters in the new password. (default 0) minclass The minimum number of required classes of characters for the new password (digits, uppercase, lowercase, others). (default 0) maxrepeat The maximum number of allowed same consecutive characters in the new password. The check is disabled if the value is 0. (default 0) maxsequence The maximum length of monotonic character sequences in the new password. Examples of such sequence are '12345' or 'fedcb'. Note that most such passwords will not pass the simplicity check unless the sequence is only a minor part of the password. The check is disabled if the value is 0. (default 0) maxclassrepeat The maximum number of allowed consecutive characters of the same class in the new password. The check is disabled if the value is 0. (default 0) gecoscheck If nonzero, check whether the words longer than 3 characters from the GECOS field of the user's passwd(5) entry are contained in the new password. The check is disabled if the value is 0. (default 0) dictcheck If nonzero, check whether the password (with possible modifications) matches a word in a dictionary. Currently the dictionary check is performed using the cracklib library. (default 1) badwords Space separated list of words that must not be contained in the password. These are additional words to the cracklib dictionary check. This setting can be also used by applications to emulate the gecos check for user accounts that are not created yet. dictpath Path to the cracklib dictionaries. Default is to use the cracklib default.
pwscore(1), pwmake(1), pam_pwquality(8)
Tomas Mraz <tmraz@redhat.com>
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