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Chapter 3. Securing the Management Interfaces with LDAP
The Management Interfaces can authenticate against an LDAP server (including Microsoft Active Directory) instead of the property-file based security realms configured by default. This is accomplished by using an LDAP authenticator. An LDAP authenticator operates by first establishing a connection (using an outbound LDAP connection) to the remote directory server. It then performs a search using the username which the user passed to the authentication system, to find the fully-qualified distinguished name (DN) of the LDAP record. If successful, a new connection is established, using the DN of the user as the credential, and password supplied by the user. If this second connection and authentication to the LDAP server is successful, the DN is verified to be valid and authentication has succeeded.
Securing the Management Interfaces with LDAP changes the authentication from digest to BASIC/Plain, which by default, will cause usernames and passwords to be sent over the network in the clear. SSL/TLS can be enabled on the outbound connection to encrypt this traffic and avoid sending this information in the clear.
3.1. Basic setup
To use an LDAP directory server as the authentication source for any or all of the management interfaces, the following procedures must be performed:
3.1.1. 1. Creating an Outbound Connection to the LDAP Server
The purpose of creating an outbound LDAP connection is to allow the security realm (and the JBoss EAP instance) to establish a connection to the LDAP server. This is similar to the case of creating a datasource for use with the Database login module in a security domain.
The LDAP outbound connection allows the following attributes:
| Attribute | Required | Description |
|---|---|---|
| url | yes | The URL address of the directory server. |
| search-dn | no | The fully distinguished name (DN) of the user authorized to perform searches. |
| search-credential | no | The password of the user authorized to perform searches. |
| initial-context-factory | no | The initial context factory to use when establishing the connection. Defaults to com.sun.jndi.ldap.LdapCtxFactory. |
| security-realm | no | The security realm to reference to obtain a configured SSLContext to use when establishing the connection. |
| referrals | no | Specifies the behavior when encountering a referral when doing a search. Valid options are IGNORE, FOLLOW, and THROW. INGORE (default behavior) simply ignores the referral. If set to FOLLOW, when referrals are encountered during a search, the DirContext being used will attempt to follow that referral. This assumes the same connection settings can be used to connect to the second server and the name used in the referral is reachable. If set to THROW, then the DirContext will throw an exception (LdapReferralException) to indicate that a referral is required, which the security realm will handle and attempt to identify an alternative connection to use for the referral. |
| handles-referrals-for | no | Specifies the referrals a connection can handle. If specifying list of URIs, they should be separated by spaces. This enables a connection with connection properties to be defined and used when different credentials are needed to follow a referral. This is useful in situations where different credentials are needed to authenticate against the second server or for situations where the server returns a name in the referral that is not reachable from the JBoss EAP 6 installation and an alternative address can be substituted. |
The search-dn and search-credential are different than the username and password provided by the user. The information provided here is specifically for establishing an initial connection between the JBoss EAP instance and the LDAP server. This connection allows JBoss EAP to perform a subsequent search for the DN of the user trying to authenticate. The DN of the user (which is a result of the search) trying to authenticate and the password they provided are used to establish a second (and separate) connection for completing the authentication process.
Given the example LDAP server, below are the CLI commands and resulting XML configuration for configuring an outbound LDAP connection to it:
| Attribute | Value |
|---|---|
| url | 127.0.0.1:389 |
| search-credential | myPass |
| search-dn | cn=search,dc=acme,dc=com |
CLI for Adding the Outbound Connection
/core-service=management/ldap-connection=ldap-connection/:add( \ search-credential=myPass, \ url=ldap://127.0.0.1:389, \ search-dn="cn=search,dc=acme,dc=com")
reload
Resulting XML
<outbound-connections>
<ldap name="ldap-connection"
url="ldap://127.0.0.1:389"
search-dn="cn=search,dc=acme,dc=com"
search-credential="myPass"/>
</outbound-connections>
The above CLI commands were done assuming a standalone instance of JBoss EAP 6. For more details on using the CLI with JBoss EAP 6 domains, please consult The Management CLI section of the Red Hat JBoss Enterprise Application Platform 6 Administration and Configuration Guide.
This creates an clear connection between the JBoss EAP instance and the LDAP server. For more details on setting up an encrypted connection using SSL/TLS, please see the Section 3.2, “Using SSL/TLS for the Outbound LDAP Connection”.
3.1.2. 2. Creating a new LDAP-Enabled Security Realm
Once the outbound LDAP connection has been created, a new LDAP-Enabled security realm must be created to use it.
The LDAP security realm has the following configuration attributes:
| Attribute | Description |
|---|---|
| connection | The name of the connection defined in outbound-connections to use to connect to the LDAP directory. |
| base-dn | The distinguished name of the context to begin searching for the user. |
| recursive | Whether the search should be recursive throughout the LDAP directory tree, or only search the specified context. Defaults to false. |
| user-dn | The attribute of the user that holds the distinguished name. This is subsequently used to test authentication as the user can complete. Defaults to dn. |
| allow-empty-passwords | This attribute determines whether an empty password is accepted. The default value for this attribute is false. |
| username-attribute | Either username-attribute or advanced-filter must be specified. The name of the attribute to search for the user. This filter performs a simple search where the user name entered by the user matches the specified attribute. |
| advanced-filter | Either username-attribute or advanced-filter must be specified. The fully defined filter used to search for a user based on the supplied user ID. This attribute contains a filter query in standard LDAP syntax. The filter must contain a variable in the following format: {0}. This is later replaced with the user name supplied by the user. More specifics and examples on using advanced-filter can be found in the <advanced-filter> part of the Combining LDAP and RBAC for Authorization section. |
It is important to ensure that empty LDAP passwords are not allowed since it is a serious security concern. Unless this behavior is specifically desired in the environment, ensure empty passwords are not allowed and allow-empty-passwords remains false.
Here are the CLI commands and resulting XML configuration for configuring an LDAP-enabled security realm using the ldap-connection outbound LDAP connection.
CLI
/core-service=management/security-realm=ldap-security-realm:add
/core-service=management/security-realm=ldap-security-realm/authentication=ldap:add( \ connection="ldap-connection", base-dn="cn=users,dc=acme,dc=com", \ username-attribute="sambaAccountName")
reload
Resulting XML
<security-realm name="ldap-security-realm">
<authentication>
<ldap connection="ldap-connection" base-dn="cn=users,dc=acme,dc=com">
<username-filter attribute="sambaAccountName"/>
</ldap>
</authentication>
</security-realm>
The above CLI commands were done assuming a standalone instance of JBoss EAP 6. For more details on using the CLI with JBoss EAP 6 domains, please consult The Management CLI section of the Red Hat JBoss Enterprise Application Platform 6 Administration and Configuration Guide.
3.1.3. 3. Reference the new security realm in the Management Interface
Once a security realm has been created and is using the outbound LDAP connection, that new security realm must be referenced by the management interfaces.
CLI Command for Updating the HTTP Interface
/core-service=management/management-interface=http-interface/:write-attribute( \ name=security-realm,value="ldap-security-realm")
CLI Command for Updating the Native Interface
/core-service=management/management-interface=native-interface/:write-attribute( \ name=security-realm,value="ldap-security-realm")
Resulting XML
<management-interfaces>
<native-interface security-realm="ldap-security-realm">
<socket-binding native="management-native"/>
</native-interface>
<http-interface security-realm="ldap-security-realm">
<socket-binding http="management-http"/>
</http-interface>
</management-interfaces>
The above CLI commands were done assuming a standalone instance of JBoss EAP 6. For more details on using the CLI with JBoss EAP 6 domains, please consult The Management CLI section of the Red Hat JBoss Enterprise Application Platform 6 Administration and Configuration Guide.
3.2. Using SSL/TLS for the Outbound LDAP Connection
JBoss EAP 6 can be configured to use an outbound connection to an LDAP server using SSL/TLS. To create an outbound LDAP connection secured by SSL/TLS, the following procedures must be performed:
3.2.1. 1. Configuring a Security Realm for the Outbound LDAP Connection to Use
The security realm must contain a keystore configured with the key that the JBoss EAP 6 server will use to decrypt/encrypt communications between itself and the LDAP server. This keystore will also allow the JBoss EAP 6 instance to verify itself against the LDAP server. The security realm must also contain a truststore that contains the LDAP server’s certificate (or the certificate of the certificate authority used to sign the LDAP server’s certificate). See Setting up 2-Way SSL/TLS for the Management Interfaces in the JBoss EAP 6 How to Configure Server Security guide for instructions on configuring keystores and truststores and creating a security realm that uses them.
3.2.2. 2. Create an Outbound LDAP Connection with the SSL/TLS URL and Security Realm
Similar to the process defined in Creating an Outbound Connection to the LDAP Server, an outbound LDAP connection should be created, but using the SSL/TLS URL for the LDAP server and the SSL/TLS security realm.
Once the outbound LDAP connection and SSL/TLS security realm for the LDAP server have been created, the the outbound LDAP connection needs to be updated with that information.
Example CLI for Adding the Outbound Connection with an SSL/TLS URL
/core-service=management/ldap-connection=ldap-connection/:add( \ search-credential=myPass, \ url=ldaps://LDAP_HOST:LDAP_PORT, \ search-dn="cn=search,dc=acme,dc=com")
Adding the security realm with the SSL/TLS certificates
/core-service=management/ldap-connection=ldap-connection:write-attribute( \ name=security-realm,value="CertificateRealm")
reload
Resulting XML
<outbound-connections> <ldap name="ldap-connection" url="ldaps://LDAP_HOST:LDAP_PORT" security-realm="CertificateRealm" search-dn="cn=search,dc=acme,dc=com" search-credential="myPass" /> </outbound-connections>
The above CLI commands were done assuming a standalone instance of JBoss EAP 6. For more details on using the CLI with JBoss EAP 6 domains, please consult The Management CLI section of the Red Hat JBoss Enterprise Application Platform 6 Administration and Configuration Guide.
3.2.3. 3. Creating a New Security Realm that uses the Outbound LDAP Connection for use by the Management Interfaces
Follow the procedures outlined in sections Creating a new LDAP-Enabled Security Realm and Reference the new security realm in the Management Interface.
3.3. LDAP and RBAC
RBAC (Role-Based Access Control) is a mechanism for specifying a set of permissions (roles) for a set of management users, allowing users to be granted different management responsibilities without giving them full, unrestricted access. For more specific details on RBAC, please see the Role-Based Access Control section of the Red Hat JBoss Enterprise Application Platform 6 Security Architecture guide.
RBAC is used only for authorization, with authentication being handled separately. Since LDAP can be used for authentication as well as authorization, JBoss EAP 6 may be configured to use RBAC for authorization without LDAP (using LDAP or any other mechanism for authentication). JBoss EAP 6 may also be configured to use RBAC combined with LDAP for making authorization decisions in the management interfaces.
3.3.1. Using LDAP and RBAC Independently
JBoss EAP 6 allows for authentication and authorization to be configured independently in security realms. This enables LDAP to be configured as an authentication mechanism and RBAC to be configured as an authorization mechanism. If configured in this manner, when a user attempts to access a management interface, they will first be authenticated using the configured LDAP server. If successful, the user’s role (and configured permissions of that role) will be determined using only RBAC (independent of any group information found in the LDAP server).
For more details on using just RBAC as an authorization mechanism for the management interfaces, please see the Server Security guide. For more details on configuring LDAP for authentication with the management interfaces, please see the previous section on the topic.
3.3.2. Combining LDAP and RBAC for Authorization
Users who have authenticated using an LDAP server (or using the properties file), can be members of user groups. A user group is simply an arbitrary label that can be assigned to one or more users. RBAC can be configured to use this group information to automatically assign a role to a user or exclude a user from a role.
An LDAP directory contains entries for user accounts and groups, cross referenced by attributes. Depending on the LDAP server configuration, a user entity may map the groups the user belongs to through memberOf attributes; a group entity may map which users belong to it through uniqueMember attributes; or a combination of the two. Once a user is successfully authenticated to the LDAP server, a group search is performed to load that user’s group information. Depending on the directory server in use, group searches can be performed using their simple name (usually the username used in authentication) or by using the distinguished name of the user’s entry in the directory. Group searches (<group-search>) as well as mapping between a username and a distinguished name (<username-to-dn>) are configured when setting up LDAP as an authorization mechanism in a security realm.
Once a user’s group membership information is determined from the LDAP server, a mapping within the RBAC configuration is used to determine what role(s) a user has. This mapping is configured to explicitly include or exclude groups as well as individual users.
The authentication step of a user connecting to the server always happens first. Once the user is successfully authenticated the server loads the user’s groups. The authentication step and the authorization step each require a connection to the LDAP server. The security realm optimizes this process by reusing the authentication connection for the group loading step.
3.3.2.1. Using group-search
There are two different styles that can be used when searching for group membership information: Principal to Group and Group to Principal. Principal to Group has the user’s entry containing references to the group(s) it is a member of (i.e. memberOf attribute). Group to Principal has the group’s entry contain the references to the user(s) who are members of it (i.e. uniqueMember).
JBoss EAP 6 supports both Principal to Group as well as Group to Principal searches, but Principal to Group is recommended over Group to Principal. If Principal to Group is used, group information can be loaded directly by reading attributes of known distinguished names without having to perform any searches. Group to Principal requires extensive searches to identify the all groups that reference a user.
Both Principal to Group and Group to Principal use the <group-search> tag which contains the following attributes:
| Attribute | Description |
|---|---|
| group-name | This attribute is used to specify the form that should be used for the group name returned as the list of groups of which the user is a member. This can either be the simple form of the group name or the group’s distinguished name. If the distinguished name is required this attribute can be set to DISTINGUISHED_NAME. Defaults to SIMPLE. |
| iterative | This attribute is used to indicate if, after identifying the groups a user is a member of, we should also iteratively search based on the groups to identify which groups the groups are a member of. If iterative searching is enabled we keep going until either we reach a group that is not a member if any other groups or a cycle is detected. Defaults to false. |
| group-dn-attribute | On an entry for a group which attribute is its distinguished name. Defaults to dn. |
| group-name-attribute | On an entry for a group which attribute is its simple name. Defaults to uid. |
Cyclic group membership is not a problem. A record of each search is kept to prevent groups that have already been searched from being searched again.
For iterative searching to work the group entries need to look the same as user entries. The same approach used to identify the groups a user is a member of is then used to identify the groups of which the group is a member. This would not be possible if for group to group membership the name of the attribute used for the cross reference changes or if the direction of the reference changes.
Principal to Group (memberOf) for Group Search
Consider an example where a user TestUserOne who is a member of GroupOne, and GroupOne is in turn a member of GroupFive. The group membership would be shown by the use of a memberOf attribute at the member level. This means, TestUserOne would have a memberOf attribute set to the dn of GroupOne. GroupOne in turn would have a memberOf attribute set to the dn of GroupFive.
To use this type of searching, the principal-to-group element is added to the group-search element:
Principal to Group (i.e. memberOf) Configuration
<security-realm name="ldap-security-realm">
<authentication>
<ldap connection="ldap-connection" >
<!-- configuration -->
</ldap>
</authentication>
<authorization>
<ldap connection="ldap-connection">
<!-- configuration -->
<group-search group-name="SIMPLE" iterative="true" group-dn-attribute="dn" group-name-attribute="uid">
<principal-to-group group-attribute="memberOf" />
</group-search>
</ldap>
</authorization>
</security-realm>
Notice that within <group-search>, <principal-to-group> has been added with a group-attribute attribute. For reference:
| Attribute | Description |
|---|---|
| group-attribute | The name of the attribute on the user entry that matches the distinguished name of the group the user is a member of. Defaults to memberOf. |
| prefer-original-connection | This value is used to indicate which group information to prefer when following a referral. Each time a principal is loaded, attributes from each of their group memberships are subsequently loaded. Each time attributes are loaded, either the original connection or connection from the last referral can be used. Defaults to true. |
Group to Principal (i.e. uniqueMember) Group Search
Consider the same example as Principal to Group where a user TestUserOne who is a member of GroupOne, and GroupOne is in turn a member of GroupFive. However, in this case the group membership would be shown by the use of the uniqueMember attribute set at the group level. This means, GroupFive would have a uniqueMember set to the dn of GroupOne. GroupOne in turn would have a uniqueMember set to the dn of TestUserOne.
To use this type of searching, the group-to-principal element is added to the group-search element:
Group to Principal (i.e. uniqueMember) Configuration
<security-realm name="ldap-security-realm">
<authentication>
<ldap connection="ldap-connection" >
<!-- configuration -->
</ldap>
</authentication>
<authorization>
<ldap connection="ldap-connection">
<!-- configuration -->
<group-search group-name="SIMPLE" iterative="true" group-dn-attribute="dn" group-name-attribute="uid">
<group-to-principal base-dn="ou=groups,dc=group-to-principal,dc=example,dc=org" recursive="true" search-by="DISTINGUISHED_NAME">
<membership-filter principal-attribute="uniqueMember" />
</group-to-principal>
</group-search>
</ldap>
</authorization>
</security-realm>
Notice that within <group-search>, <group-to-principal> has been added with attributes and contains <membership-filter>. group-to-principal is used to define how searches for groups that reference the user entry will be performed, and membership-filter is used to define the cross reference.
For reference:
| Attribute | Description |
|---|---|
| base-dn | The distinguished name of the context to use to begin the search. |
| recursive | Whether sub-contexts also be searched. Defaults to false. |
| search-by | The form of the role name used in searches. Valid values are SIMPLE and DISTINGUISHED_NAME. Defaults to DISTINGUISHED_NAME. |
| prefer-original-connection | This value is used to indicate which group information to prefer when following a referral. Each time a principal is loaded, attributes from each of their group memberships are subsequently loaded. Each time attributes are loaded, either the original connection or connection from the last referral can be used. |
| Attribute | Description |
|---|---|
| principal-attribute | The name of the attribute on the group entry that references the user entry. Defaults to member. |
3.3.2.2. Using username-to-dn
It is possible to define rules within the authorization section to convert a user’s simple user name to their distinguished name. The username-to-dn element specifies how to map the user name to the distinguished name of their entry in the LDAP directory. This element is optional and only required when both of the following are true:
- The authentication and authorization steps are against different LDAP servers.
- The group search uses the distinguished name.
This could also be applicable in instances where the security realm supports both LDAP and Kerberos authentication and a conversion is needed for Kerberos, if LDAP authentication has been performed the DN discovered during authentication can be used.
It contains the following attributes:
| Attribute | Description |
|---|---|
| force | The result of a user name to distinguished name mapping search during authentication is cached and reused during the authorization query when the force attribute is set to "false". When force is true, the search is performed again during authorization (while loading groups). This is typically done when different servers perform authentication and authorization. |
username-to-dn can be configured with one of the following:
- <username-is-dn>
- This specifies that the user name entered by the remote user is the user’s distinguished name.
username-is-dn Example
<security-realm name="ldap-security-realm">
<authentication>
<ldap connection="ldap-connection" >
<!-- configuration -->
</ldap>
</authentication>
<authorization>
<ldap connection="ldap-connection">
<username-to-dn force="false">
<username-is-dn />
</username-to-dn>
<!-- configuration -->
</ldap>
</authorization>
</security-realm>
This defines a 1:1 mapping and there is no additional configuration.
- <username-filter>
- A specified attribute is searched for a match against the supplied user name.
username-filter Example
<security-realm name="ldap-security-realm">
<authentication>
<ldap connection="ldap-connection" >
<!-- configuration -->
</ldap>
</authentication>
<authorization>
<ldap connection="ldap-connection">
<username-to-dn force="true">
<username-filter base-dn="dc=people,dc=harold,dc=example,dc=com" recursive="false" attribute="sn" user-dn-attribute="dn" />
</username-to-dn>
<!-- configuration -->
</ldap>
</authorization>
</security-realm>
| Attribute | Description |
|---|---|
| base-dn | The distinguished name of the context to begin the search. |
| recursive | Whether the search will extend to sub contexts. Defaults to false. |
| attribute | The attribute of the users entry to try and match against the supplied user name. Defaults to uid. |
| user-dn-attribute | The attribute to read to obtain the users distinguished name. Defaults to dn. |
- <advanced-filter>
- This option uses a custom filter to locate the users distinguished name.
advanced-filter Example
<security-realm name="ldap-security-realm">
<authentication>
<ldap connection="ldap-connection" >
<!-- configuration -->
</ldap>
</authentication>
<authorization>
<ldap connection="ldap-connection">
<username-to-dn force="true">
<advanced-filter base-dn="dc=people,dc=harold,dc=example,dc=com" recursive="false" filter="sAMAccountName={0}" user-dn-attribute="dn" />
</username-to-dn>
<!-- configuration -->
</ldap>
</authorization>
</security-realm>
For the attributes that match those in the username-filter example, the meaning and default values are the same. There is one additional attribute:
| Attribute | Description |
|---|---|
| filter | Custom filter used to search for a user’s entry where the user name will be substituted in the {0} place holder. |
The XML must remain valid after the filter is defined so if any special characters are used (such as &) ensure the proper form is used. For example & for the & character.
3.3.2.3. Mapping LDAP Group Information to RBAC Roles
Once the connection to the LDAP server has been created and the group searching has been properly configured, a mapping needs to be created between the LDAP groups and RBAC roles. This mapping can be both inclusive as well as exclusive and enables users to be automatically assigned one or more roles based on their group membership information.
If RBAC is not already configured, pay close attention when doing so, especially if switching to a newly-created LDAP-enabled realm. Enabling RBAC without having users and roles properly configured could result in administrators being unable to login to the management interfaces.
The below CLI commands were done assuming a standalone instance of JBoss EAP 6. For more details on using the CLI with JBoss EAP 6 domains, please consult The Management CLI section of the Red Hat JBoss Enterprise Application Platform 6 Administration and Configuration Guide.
Ensure RBAC is Enabled and Configured
Before mappings between LDAP and RBAC Roles can be used, RBAC must enabled and initially configured.
/core-service=management/access=authorization:read-attribute(name=provider)
It should yield the following result:
{
"outcome" => "success",
"result" => "rbac"
}For more information on enabling and configuring RBAC, please see the Enabling Role-Based Access Control section of the Red Hat JBoss Enterprise Application Platform 6 How to Configure Server Security guide.
Verify Existing List of Roles
Use the read-children-names operation to get a complete list of the configured roles:
/core-service=management/access=authorization:read-children-names(child-type=role-mapping)
Which should yield a list of roles:
{
"outcome" => "success",
"result" => [
"Administrator",
"Deployer",
"Maintainer",
"Monitor",
"Operator",
"SuperUser"
]
}In addition, all existing mappings for a role may be checked:
/core-service=management/access=authorization/role-mapping=Administrator:read-resource(recursive=true)
{
"outcome" => "success",
"result" => {
"include-all" => false,
"exclude" => undefined,
"include" => {
"user-theboss" => {
"name" => "theboss",
"realm" => undefined,
"type" => "USER"
},
"user-harold" => {
"name" => "harold",
"realm" => undefined,
"type" => "USER"
},
"group-SysOps" => {
"name" => "SysOps",
"realm" => undefined,
"type" => "GROUP"
}
}
}
}Configure a Role-Mapping entry
If a role does not already have a Role-Mapping entry, one needs to be created. For instance:
/core-service=management/access=authorization/role-mapping=Auditor:read-resource()
{
"outcome" => "failed",
"failure-description" => "JBAS014807: Management resource '[
(\"core-service\" => \"management\"),
(\"access\" => \"authorization\"),
(\"role-mapping\" => \"Auditor\")
]' not found"
}To add a role mapping:
/core-service=management/access=authorization/role-mapping=Auditor:add()
{
"outcome" => "success"
}To verify:
/core-service=management/access=authorization/role-mapping=Auditor:read-resource()
{
"outcome" => "success",
"result" => {
"include-all" => false,
"exclude" => undefined,
"include" => undefined
}
}
Add Groups to the Role for Inclusion and Exclusion
Groups may be added for inclusion or exclusion from a role.
The exclusion mapping takes precedence or the inclusion mapping.
To add a group for inclusion:
/core-service=management/access=authorization/role-mapping=Auditor/include=group-GroupToInclude:add(name=GroupToInclude, type=GROUP)
To add a group for exclusion:
/core-service=management/access=authorization/role-mapping=Auditor/exclude=group-GroupToExclude:add(name=GroupToExclude, type=GROUP)
To check the result:
[standalone@localhost:9999 /] /core-service=management/access=authorization/role-mapping=Auditor:read-resource(recursive=true)
{
"outcome" => "success",
"result" => {
"include-all" => false,
"exclude" => {"group-GroupToExclude" => {
"name" => "GroupToExclude",
"realm" => undefined,
"type" => "GROUP"
}},
"include" => {"group-GroupToInclude" => {
"name" => "GroupToInclude",
"realm" => undefined,
"type" => "GROUP"
}}
}
}Removing a Group from a Role
Groups that are added for exclusion or inclusion may also be removed
To remove a group from inclusion:
/core-service=management/access=authorization/role-mapping=Auditor/include=group-GroupToInclude:remove
To remove a group from exclusion:
/core-service=management/access=authorization/role-mapping=Auditor/exclude=group-GroupToExclude:remove
3.4. Enabling Caching
Security Realms also offer the ability to cache the results of LDAP queries for both authentication as well as group loading. This enables the results of different queries to be reused across multiple searches by different users in certain circumstances (e.g. iteratively querying the group membership information of groups). There are three different caches available, each of which are configured separately and operate independently:
- authentication
- group-to-principal
- username-to-dn
3.4.1. Cache Configuration
Even though the caches are independent of one another, all three are configured in the same manner. Each cache offers the following configuration options:
| Attribute | Description |
|---|---|
| type | This defines the eviction straregy that the cache will adhere to. Options are by-access-time and by-search-time. by-access-time evicts items from the cache after a certain period of time has elapsed since their last access. by-search-time evicts items based on how long they have been in the cache regardless of their last access. |
| eviction-time | This defines the time (in seconds) used for evictions depending on the strategy. |
| cache-failures | This is a boolean that enables/disables the caching of failed searches. This has the potential for preventing an LDAP server from being repeatedly access by the same failed search, but it also has the potential to fill up the cache with searches for users that do not exist. This setting is particularly important for the authentication cache. |
| max-cache-size | This defines maximum size (number of items) of the cache, which in-turn dictates when items will begin getting evicted. Old items are evicted from the cache to make room for new authentication and searches as needed, meaning max-cache-size will not prevent new authentication attempts or searches from occuring. |
3.4.2. Example
This example assumes a security realm has been created named LDAPRealm that connects to an existing LDAP server and is configured for authentication and authorization. The commands to display the current configuration are detailed in a later section. More details on creating a security realm that uses LDAP can be found here.
Example Base Configuration
"core-service" : {
"management" : {
"security-realm" : {
"LDAPRealm" : {
"authentication" : {"ldap" : {
"allow-empty-passwords" : false,
"base-dn" : "...",
"connection" : "MyLdapConnection",
"recursive" : false,
"user-dn" : "dn",
"username-attribute" : "uid",
"cache" : null
}},
"authorization" : {"ldap" : {
"connection" : "MyLdapConnection",
"group-search" : {"group-to-principal" : {
"base-dn" : "...",
"group-dn-attribute" : "dn",
"group-name" : "SIMPLE",
"group-name-attribute" : "uid",
"iterative" : true,
"principal-attribute" : "uniqueMember",
"search-by" : "DISTINGUISHED_NAME",
"cache" : null
}},
"username-to-dn" : {"username-filter" : {
"attribute" : "uid",
"base-dn" : "...",
"force" : false,
"recursive" : false,
"user-dn-attribute" : "dn",
"cache" : null
}}
}},
}
}
}
In all areas where "cache" : null appear, a cache may be configured:
- Authentication
- During authentication the user’s distinguished name is discovered using this definition and an attempt to connect to the LDAP server and verify their identity is made using these credentials.
- A group-search definition
- There is the group search definition, in this case it is an iterative search (because iterative is set to true in the sample configuration above). First, a search will be performed to find all groups the user is a direct member of. After that, a search will be performed for each of those groups to identify if they have membership to other groups. This process continues until either a cyclic reference is detected or the final groups are not members of any further groups.
- A username-to-dn definition in group search
- Group searching relies on the availability of the users distinguished name. This section is not used in all situations, but it can be used as a second attempt to discover a user’s distinguished name. This, for instance, may be useful or even required when a second form of authentication was supported (e.g. local authentication).
3.4.2.1. Reading the Current Cache Configuration
The CLI commands used in this and subsequent sections use LDAPRealm for the name of the security realm. This should be substituted for the name of the actual realm being configured.
CLI Command to Read the Current Cache Configuration
/core-service=management/security-realm=LDAPRealm:read-resource(recursive=true)
Output
{
"outcome" => "success",
"result" => {
"map-groups-to-roles" => true,
"authentication" => {"ldap" => {
"advanced-filter" => undefined,
"allow-empty-passwords" => false,
"base-dn" => "dc=example,dc=com",
"connection" => "ldapConnection",
"recursive" => true,
"user-dn" => "dn",
"username-attribute" => "uid",
"cache" => undefined
}},
"authorization" => {"ldap" => {
"connection" => "ldapConnection",
"group-search" => {"principal-to-group" => {
"group-attribute" => "description",
"group-dn-attribute" => "dn",
"group-name" => "SIMPLE",
"group-name-attribute" => "cn",
"iterative" => false,
"prefer-original-connection" => true,
"skip-missing-groups" => false,
"cache" => undefined
}},
"username-to-dn" => {"username-filter" => {
"attribute" => "uid",
"base-dn" => "ou=Users,dc=jboss,dc=org",
"force" => true,
"recursive" => false,
"user-dn-attribute" => "dn",
"cache" => undefined
}}
}},
"plug-in" => undefined,
"server-identity" => undefined
}
}
3.4.2.2. Enabling a Cache
The CLI commands used in this and subsequent sections configure the cache in the authentication portion of the security realm (i.e. /authentication=ldap/). Caches in the authorization portion may also be configured in a similar manner by updating the path of the command.
CLI for Enabling a Cache
/core-service=management/security-realm=LDAPRealm/authentication=ldap/cache=by-access-time:add( \ eviction-time=300, cache-failures=true, max-cache-size=100)
This commands adds a by-access-time cache for authentication with an eviction time of 300 seconds (5 minutes) and a max cache size of 100 items. In addition, failed searches will be cached. Alternatively, a by-search-time cache could also be configured:
/core-service=management/security-realm=LDAPRealm/authentication=ldap/cache=by-search-time:add( \ eviction-time=300, cache-failures=true, max-cache-size=100)
3.4.2.3. Inspecting an Existing Cache
CLI for Inspecting an Existing Cache
/core-service=management/security-realm=LDAPRealm/authentication=ldap/cache=by-access-time:read-resource(include-runtime=true)
Output
{
"outcome" => "success",
"result" => {
"cache-failures" => true,
"cache-size" => 1,
"eviction-time" => 300,
"max-cache-size" => 100
}
}
The include-runtime attribute adds the cache-size element, which displays the current number of items in the cache (1 in this case).
3.4.2.4. Testing an Existing Cache’s Contents
CLI for Testing an Existing Cache’s Contents
/core-service=management/security-realm=LDAPRealm/authentication=ldap/cache=by-access-time:contains(name=TestUserOne)
Output
{
"outcome" => "success",
"result" => true
}
This shows that an entry for TestUserOne exists the in the cache.
3.4.2.5. Flushing a Cache
An entire cache may be flushed as can individual items from a cache.
CLI for Flushing a Single Item
/core-service=management/security-realm=LDAPRealm/authentication=ldap/cache=by-access-time:flush-cache(name=TestUserOne)
CLI for Flushing an Entire Cache
/core-service=management/security-realm=LDAPRealm/authentication=ldap/cache=by-access-time:flush-cache()
3.4.2.6. Removing a Cache
CLI for Removing a Cache
/core-service=management/security-realm=LDAPRealm/authentication=ldap/cache=by-access-time:remove()
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