openldap-2.5.4

ppm.c - OpenLDAP password policy module version 2.0 ppm.c is an OpenLDAP module for checking password quality when they are modified. Passwords are checked against the presence or absence of certain character classes. This module is used as an extension of the OpenLDAP password policy controls, see slapo-ppolicy(5) section pwdCheckModule. contributions ------------- * 2014 - 2021 - David Coutadeur <david.coutadeur@gmail.com> - maintainer * 2015 - Daly Chikhaoui - Janua <dchikhaoui@janua.fr> - contribution on RDN checks * 2017 - tdb - Tim Bishop - contribution on some compilation improvements INSTALLATION ------------ See INSTALL file USAGE ----- Create a password policy entry and indicate the path of the ppm.so library and the content of the desired policy. Use a base64 tool to code / decode the content of the policy stored into pwdCheckModuleArg. Here is an example: ``` dn: cn=default,ou=policies,dc=my-domain,dc=com objectClass: pwdPolicy objectClass: top objectClass: pwdPolicyChecker objectClass: person pwdCheckQuality: 2 pwdAttribute: userPassword sn: default cn: default pwdMinLength: 6 pwdCheckModule: /usr/local/lib/ppm.so pwdCheckModuleArg:: bWluUXVhbGl0eSAzCmNoZWNrUkROIDAKZm9yYmlkZGVuQ2hhcnMKbWF4Q29uc2VjdXRpdmVQZXJDbGFzcyAwCnVzZUNyYWNrbGliIDAKY3JhY2tsaWJEaWN0IC92YXIvY2FjaGUvY3JhY2tsaWIvY3JhY2tsaWJfZGljdApjbGFzcy11cHBlckNhc2UgQUJDREVGR0hJSktMTU5PUFFSU1RVVldYWVogMCAxCmNsYXNzLWxvd2VyQ2FzZSBhYmNkZWZnaGlqa2xtbm9wcXJzdHV2d3h5eiAwIDEKY2xhc3MtZGlnaXQgMDEyMzQ1Njc4OSAwIDEKY2xhc3Mtc3BlY2lhbCA8Piw/Oy46LyHCp8O5JSrCtV7CqCTCo8KyJsOpfiIjJ3soWy18w6hgX1zDp17DoEApXcKwPX0rIDAgMQ== ``` See slapo-ppolicy for more information, but to sum up: - enable ppolicy overlay in your database. This example show the activation for a slapd.conf file (see slapd-config and slapo-ppolicy for more information for cn=config configuration) ``` overlay ppolicy ppolicy_default "cn=default,ou=policies,dc=my-domain,dc=com" #ppolicy_use_lockout # for having more infos about the lockout ``` - define a default password policy in OpenLDAP configuration or use pwdPolicySubentry attribute to point to the given policy. Password checks --------------- - 4 character classes are defined by default: upper case, lower case, digits and special characters. - more character classes can be defined, just write your own. - passwords must match the amount of quality points. A point is validated when at least m characters of the corresponding character class are present in the password. - passwords must have at least n of the corresponding character class present, else they are rejected. - the two previous criteria are checked against any specific character class defined. - if a password contains any of the forbidden characters, then it is rejected. - if a password contains tokens from the RDN, then it is rejected. - if a password is too long, it can be rejected. - if a password does not pass cracklib check, it can be rejected. Configuration ------------- Since OpenLDAP 2.5 version, ppm configuration is held in a binary attribute of the password policy: pwdCheckModuleArg The example file (/etc/openldap/ppm.example by default) is to be considered as an example configuration, to import in the pwdCheckModuleArg attribute. It is also used for testing passwords with the test program provided. If for some reasons, any parameter is not found, it will be given its default value. Note: you can still compile ppm to use the configuration file, by enabling PPM_READ_FILE in ppm.h (but this is deprecated now). If you decide to do so, you can use the PPM_CONFIG_FILE environment variable for overloading the configuration file path. The syntax of a configuration line is: parameter value [min] [minForPoint] with spaces being delimiters and Line Feed (LF) ending the line. Parameter names ARE case sensitive. The default configuration is the following: ``` # minQuality parameter # Format: # minQuality [NUMBER] # Description: # One point is granted for each class for which MIN_FOR_POINT criteria is fulfilled. # defines the minimum point numbers for the password to be accepted. minQuality 3 # checkRDN parameter # Format: # checkRDN [0 | 1] # Description: # If set to 1, password must not contain a token from the RDN. # Tokens are separated by the following delimiters : space tabulation _ - , ; £ checkRDN 0 # forbiddenChars parameter # Format: # forbiddenChars [CHARACTERS_FORBIDDEN] # Description: # Defines the forbidden characters list (no separator). # If one of them is found in the password, then it is rejected. forbiddenChars # maxConsecutivePerClass parameter # Format: # maxConsecutivePerClass [NUMBER] # Description: # Defines the maximum number of consecutive character allowed for any class maxConsecutivePerClass 0 # useCracklib parameter # Format: # useCracklib [0 | 1] # Description: # If set to 1, the password must pass the cracklib check useCracklib 0 # cracklibDict parameter # Format: # cracklibDict [path_to_cracklib_dictionary] # Description: # directory+filename-prefix that your version of CrackLib will go hunting for # For example, /var/pw_dict resolves as /var/pw_dict.pwd, # /var/pw_dict.pwi and /var/pw_dict.hwm dictionary files cracklibDict /var/cache/cracklib/cracklib_dict # classes parameter # Format: # class-[CLASS_NAME] [CHARACTERS_DEFINING_CLASS] [MIN] [MIN_FOR_POINT] # Description: # [CHARACTERS_DEFINING_CLASS]: characters defining the class (no separator) # [MIN]: If at least [MIN] characters of this class is not found in the password, then it is rejected # [MIN_FOR_POINT]: one point is granted if password contains at least [MIN_FOR_POINT] character numbers of this class class-upperCase ABCDEFGHIJKLMNOPQRSTUVWXYZ 0 1 class-lowerCase abcdefghijklmnopqrstuvwxyz 0 1 class-digit 0123456789 0 1 class-special <>,?;.:/!§ù%*µ^¨$£²&é~"#'{([-|è`_\ç^à@)]°=}+ 0 1 ``` Example ------- With this policy: ``` minQuality 4 forbiddenChars .?, checkRDN 1 class-upperCase ABCDEFGHIJKLMNOPQRSTUVWXYZ 0 5 class-lowerCase abcdefghijklmnopqrstuvwxyz 0 12 class-digit 0123456789 0 1 class-special <>,?;.:/!§ù%*µ^¨$£²&é~"#'{([-|è`_\ç^à@)]°=}+ 0 1 class-myClass :) 1 1`` ``` the password ThereIsNoCowLevel) is working, because, - it has 4 character classes validated : upper, lower, special, and myClass - it has no character among .?, - it has at least one character among : or ) but it won't work for the user uid=John Cowlevel,ou=people,cn=example,cn=com, because the token "Cowlevel" from his RDN exists in the password (case insensitive). Logs ---- If a user password is rejected by ppm, the user will get this type of message: Typical user message from ldappasswd(5): Result: Constraint violation (19) Additional info: Password for dn=\"%s\" does not pass required number of strength checks (2 of 3) A more detailed message is written to the server log. Server log: ``` Feb 26 14:46:10 debian-10-64 slapd[1981]: conn=1000 op=16 MOD dn="uid=user,ou=persons,dc=my-domain,dc=com" Feb 26 14:46:10 debian-10-64 slapd[1981]: conn=1000 op=16 MOD attr=userPassword Feb 26 14:46:10 debian-10-64 slapd[1981]: ppm: entry uid=user,ou=persons,dc=my-domain,dc=com Feb 26 14:46:10 debian-10-64 slapd[1981]: ppm: Reading pwdCheckModuleArg attribute Feb 26 14:46:10 debian-10-64 slapd[1981]: ppm: RAW configuration: # minQuality parameter#012# Format:#012# minQuality [NUMBER]#012# Description:#012# One point is granted for each class for which MIN_FOR_POINT criteria is fulfilled.#012# defines the minimum point numbers for the password to be accepted.#012minQuality 3#012#012# checkRDN parameter#012# Format:#012# checkRDN [0 | 1]#012# Description:#012# If set to 1, password must not contain a token from the RDN.#012# Tokens are separated by the following delimiters : space tabulation _ - , ; £#012checkRDN 0#012#012# forbiddenChars parameter#012# Format:#012# forbiddenChars [CHARACTERS_FORBIDDEN]#012# Description:#012# Defines the forbidden characters list (no separator).#012# If one of them i