Connecting to a PosixAccount external LDAP directory

Step 1: Selecting the directory

Select the LDAP base of your choice. This is the first step in the configuration of this directory.

Select the option Connect to a PosixAccount external LDAP directory and click on Next.

Step 2: Accessing the directory

 

Domain name Name enabling the identification of the internal LDAP directory when several directories have been defined on the firewall. In a configuration containing multiple directories, this name will be needed in addition to the user's login for authentication (login@domain_name). You are therefore strongly advised to enter a DNS domain name in this field.
Server

Select an object corresponding to your LDAP server from the drop-down list. This object has to be created prior to this step and must reference the IP address of your LDAP server.

Port

Enter the listening port of your LDAP server. The default port is: TCP/389 (ldap object).

Root domain (Base DN)

Enter the root domain (DN) of your directory. The DN represents the name of an entry, in the form of a path to it, from the top to the bottom of the tree structure. The field can be entered using the name of the Root Domain (DN).

 

Example of a DN

AD domain is “company.com” so my Root domain (Base DN) should be “dc=company,dc=com”

Anonymous connection

If this option is selected, the connection to the LDAP directory will not require the use of an identifier and its associated password. In this case, the identifier and password fields will be grayed out.

Username

An administrator account allowing the firewall to connect to your LDAP server and make changes (reading and writing privileges) to certain fields.

We recommend that you create a specific account for the firewall and assign privileges to it only in the necessary fields.

 

Example

cn=id

Password

The password associated with the ID for you to connect to the LDAP server.

NOTE

The key icon () allows you to view the password in plaintext to check that it is correct.

REMARK

Connections to a PosixAccount external directory must be carried out in read-only mode. Users or groups therefore cannot be created from the firewall's web administration interface.

 

Click on Finish to display the external LDAP directory screen.

External LDAP directory screen

Once the configuration of the LDAP directory is complete, you will arrive at the external LDAP screen which sets out the following items:

“Configuration” tab

The page that appears presents a window that summarizes the information entered for your external LDAP and various services concerning access to your directory.

Remote directory

Enable user directory

This option allows starting the LDAP service.

If this option is not selected, the module will be inactive.

Server

This field contains the name of the server that you had entered in the previous page.

Port

This field contains the listening port that you had selected in the previous page.

Root domain (Base DN)

The root domain of your directory as it was defined when it was created.

 

Example

dc=company,dc=org

Username

The login name allowing the firewall to connect to your LDAP server.

Password

The password created in the firewall for connecting to the LDAP server.

Secure connection (SSL)

Enable SSL access

This option allows checking your digital certificate generated by the firewall’s root CA.

Information is encrypted in SSL. This method uses port 636.

Public access to the LDAP is protected by the SSL protocol.

NOTE

If this option is not selected, access will not be encrypted.

Check the certificate against a Certification Authority

During a connection to the LDAP database, the firewall will check that the certificate has been issued by the Certification Authority specified below.

Certificate authority

This option allows selecting the CA which will be used for verifying the server certificate issued by the LDAP server, in order to ensure the authenticity of the connection to this server.

Click on the magnifying glass icon () to search for the corresponding CA.

NOTE

This option will be grayed out by default if the previous option Check that the name of the server matches the FQDN in the SSL certificate was not selected.

Advanced properties

Backup server

This field allows defining a replacement server in the event the main server fails. You can select it from the list of objects suggested in the drop-down list.

By clicking on the button Test access to the directory below it, a window will inform you that your main server is functional.

Click on OK.

Use the firewall account to check user authentication on the directory

When this option is selected, the firewall will use the identifier declared during the creation of the directory in order to verify a user's privileges with the LDAP server when the user authenticates.

 

Otherwise, the firewall will use the user's account to perform this verification.

Click on Apply to confirm your configuration.

“Structure” tab

Read-only access

User selection filter

When using the firewall in interaction with an external database, only

users that match the filter will be used. By default this filter corresponds to ObjectClass = InetOrgPerson.

User group selection filter

When using the firewall in interaction with an external database, only

user groups that match the filter will be used. By default this filter corresponds to ObjectClass = PosixGroup.

You are accessing the directory in read-only mode. The creation of users and groups will not be allowed: since connections to external POSIX LDAP directories must be in read-only, this option will be automatically selected and grayed out.

Mapped attributes

Apply a model: This button offers you 3 choices of LDAP servers, which you will apply to define your attributes:

  • OpenLDAP: LDAP server.
  • Microsoft Active Directory (AD): LDAP directory services for Windows operating systems.
  • Open Directory: directory of websites under license of Open Directory

 

External directory attributes

This column represents the value given to the attribute in the external directory. For PosixAccount LDAP directories, the attribute Stormshield member will have the value memberUid.

Advanced properties

Password hash: The password encryption method for new users.

Some authentication methods (such as LDAP) have to store the user’s password in the form of a hash (result of a hash function applied to the password) which will avoid having to store the password in plaintext.

You have to select your desired hash method from the following:

SHA

“Secure Hash Algorithm”. This encryption method allows establishing a 160-bit or 160-byte character string (called a “key”) which will be used as a reference for identification.

 

MD5

“Message Digest”. This algorithm allows checking the integrity of data entered, by generating a 128-bit MD5 key.

REMARK

As this method uses fewer bytes and as such has a lower level of security, it is less robust against attacks.

SSHA

“Salt Secure Hash Algorithm”. Based on the same principle as SHA, but contains a password salting function in addition, which consists of adding a bit sequence to the data entered in order to make them less legible.

NOTE

This variant of SHA uses a random value to diversify the password’s fingerprint. Two identical passwords will therefore have two different fingerprints.

 

The encryption method is the most secure and you are strongly advised to use it.

SMD5

“Salt Message Digest”. Based on the same principle as MD5, with the addition of the password salting function.

CRYPT

The password is protected by the CRYPT algorithm, derived from the DES algorithm which allows block encryption using 56-bit keys.

 

This method is not highly advised, as it has a relatively low level of security.

None

No password encryption, meaning it is stored in plaintext.

WARNING

This method is not recommended, as your data will not be protected.

 

User branch

For PosixAccount external directories, this field is not available.

Group branch

For PosixAccount external directories, this field is not available.

Certification authority branch

This field defines the location of the CA on the external LDAP base. This location is used especially when searching for the CA used in SSL.

NOTE

Configuring this field is not absolutely necessary but in this case, in order for the SSL authentication method to work the CA has to be specified in the list of trusted CAs in the configuration of the SSL method.

 

(See menu Users\Authentication module\Available methods tab: the authentication method Certificate (SSL) has to be added and the CA indicated in the right column “Certificate authorities (C.A)” )

Click on Apply to confirm your configuration.