Autenticação LDAP

A vantagem de utilizar LDAP é que todas as informações de utilizadores e grupos podem estar armazenadas num servidor gerido a nível central.

The first thing to do is to install the php ldap extension on your linux system:

apt install php7.4-ldap

Then, in order to enable the LDAP support Lizmap, you have to change the authentication method in the configuration as follows.

Enabling LDAP

You have to enable the module ldapdao with this command

php lizmap/install/configurator.php ldapdao

Then you have to add a section [ldap:lizmapldap] into your profiles.ini.php, with some settings that allow to connect to your ldap server, and to search users into the ldap. The section may already exist if you copied profiles.ini.php from the profiles.ini.php.dist.

[ldap:lizmapldap]
hostname=localhost
port=389
adminUserDn="cn=admin,ou=lizmap,dc=com"
adminPassword=""
searchUserBaseDN="dc=XY,dc=fr"
searchUserFilter="(&(objectClass=posixAccount)(uid=%%LOGIN%%))"
bindUserDN="uid=%?%,ou=users,dc=XY,dc=fr"
searchAttributes="uid:login,givenName:firstname,sn:lastname,mail:email,organization:organization,street:street,postcode:postcode,city:city"
searchGroupFilter=
searchGroupProperty="cn"
searchGroupBaseDN=""

See details about how to set these parameters in a section below.

To finish to enable the module, run php lizmap/install/installer.php

ldap settings

Configuration properties for user data

To verify password, or to register the user into Lizmap the first time he authenticate himself, the plugin needs some data about the user.

You should indicate to it which ldap attributes it can retrieve, and which database fields that will receive the ldap attributes values.

You indicate such informations into the searchAttributes property. It is a pair of names, <ldap attribute>:<table field>, separated by a comma.

In this example, searchAttributes="uid:login,firstname,sn:lastname,mail:email,dn:":

  • the value of the uid ldap attribute will be stored into the login field

  • the value of the sn ldap attribute will be stored into the lastname field

  • the value of the firstname ldap attribute will be stored into a field that have the same name, as there is no field name nor :.

  • there will not be mapping for the dn property. There is a : without field name. It will be readed from ldap, and can be used into the bindUserDN DN template. (see below).

The list of possible fields in Lizmap are: login, email, firstname, lastname, organization, phonenumber, street, postcode, city, country. Only login and email are required. Others are optional.

Configuration properties for authentication

Before to try to authenticate the user against the ldap, the plugin retrieves user properties. It uses two configuration parameters : searchUserFilter and searchAttributes.

The searchUserFilter should contain the ldap query, and a %%LOGIN%% placeholder that will be replaced by the login given by the user.

Example: searchUserFilter="(&(objectClass=posixAccount)(uid=%%LOGIN%%))"

You may also indicate the base DN for the search, into searchUserBaseDN. Example: searchUserBaseDN="ou=ADAM users,o=Microsoft,c=US".

Note that you can indicate several search filters, if you have complex ldap structure. Use [] to indicate an item list:

searchUserFilter[]="(&(objectClass=posixAccount)(uid=%%LOGIN%%))"
searchUserFilter[]="(&(objectClass=posixAccount)(cn=%%LOGIN%%))"

To verify the password, the plugin needs the DN (Distinguished Name) corresponding to the user. It builds the DN from a «template» indicated into the bindUserDN property, and from various data. These data can be the given login or one of the ldap attributes of the user.

  • Building the DN from the login given by the user: bindUserDN should contain a DN, with a %%LOGIN%% placeholder that will be replaced by the login.

    Example: bindUserDN="uid=%%LOGIN%%,ou=users,dc=XY,dc=fr". If the user give john.smith as a login, the authentication will be made with the DN bindUserDN="uid=john.smith,ou=users,dc=XY,dc=fr".

    For some LDAP, the DN could be a simple string, for example an email. You could then set bindUserDN="%%LOGIN%%@company.local". Or even bindUserDN="%%LOGIN%%" if the login can type the full value of the DN or an email or else.. (Probably it’s not recommended to allow a user to type himself its full DN, it can be a security issue)

  • Building the DN from one of the ldap attributes of the user. In this case, the plugin will first query the ldap directory with the searchUserFilter filter, to retrieve the user’s ldap attributes. Then, in bindUserDN, you can indicate a DN where some values will be replaced by some attributes values, or you can indicate a single attribute name, corresponding to an attribute that contain the full DN of the user.

    For the first case, bindUserDn should contain a DN, with some %?% placeholders that will be replaced by corresponding attributes value. Example: bindUserDN="uid=%?%,ou=users,dc=XY,dc=fr". Here it replaces the %?% by the value of the uid attribute readed from the user’s attributes. The attribute name should be present into the searchAttributes configuration property, even with no field mapping. Ex: ...,uid:,.... See above.

    For the second case, just indicate the attribute name, prefixed with a $. Example: bindUserDN="$dn". Here it takes the dn attribute readed from the search, and use its full value as the DN to login against the ldap server. It is useful for some LDAP server like sometimes Active Directory that need a full DN specific for each user. The attribute name should be present into the searchAttributes configuration property, even with no field mapping. Ex: ...,dn:,.... See above.

Note that you can indicate several dn templates, if you have complex ldap structure. Use [] to indicate an item list:

bindUserDN[]="uid=%?%,ou=users,dc=XY,dc=fr"
bindUserDN[]="cn=%?%,ou=users,dc=XY,dc=fr"

Configuração das propriedades para os direitos de utilizador

If you have configured groups rights into Lizmap, and if these groups match your ldap groups, you can indicate to the plugin to automatically put the user into the application groups, according to the user ldap groups.

You should then indicate into searchGroupFilter the ldap query that will retrieve the groups of the user.

Example: searchGroupFilter="(&(objectClass=posixGroup)(member=%%USERDN%%))"

%%USERDN%% is replaced by the user dn. %%LOGIN%% is replaced by the login. You can also use any ldap attributes you indicate into searchAttributes, between %%. Example: searchGroupFilter="(&(objectClass=posixGroup)(member=%%givenName%%))"

Warning : setting searchGroupFilter will remove the user from any other application groups that don’t match the ldap group. If you don’t want a groups synchronization, leave searchGroupFilter empty.

With searchGroupProperty, you must indicate the ldap attribute that contains the group name. Ex: searchGroupProperty="cn".

You may also indicate the base DN for the search, into searchGroupBaseDN. Example: searchGroupBaseDN="ou=Groups,dc=Acme,dc=pt".

Debugging

If the authentication does not working, you can have more details on what is wrong. To see these details, you should activate the traces for ldapdao.

In your var/config/localconfig.ini.php, set these parameters

[logger]
auth=file

[fileLogger]
auth=auth.log

Then, in var/log/auth.log, you will have some messages from the ldap connector. Remove these settings when you don’t need them, to avoid a huge auth.log file.