This appendix provides a reference to the elements available in the security namespace and information on the underlying beans they create (a knowledge of the individual classes and how they work together is assumed - you can find more information in the project Javadoc and elsewhere in this document). If you haven't used the namespace before, please read the introductory chapter on namespace configuration, as this is intended as a supplement to the information there. Using a good quality XML editor while editing a configuration based on the schema is recommended as this will provide contextual information on which elements and attributes are available as well as comments explaining their purpose.
The <http>
element encapsulates the security configuration for the web layer of your application.
It creates a FilterChainProxy
bean named "springSecurityFilterChain" which maintains the stack of
security filters which make up the web security configuration [4]. Some core filters are always created and others will
be added to the stack depending on the attributes child elements which are present. The positions of the standard
filters are fixed (see the filter order table in the namespace introduction),
removing a common source of errors with previous versions of the framework when users had to configure the
filter chain explicitly in theFilterChainProxy
bean. You can, of course, still do this
if you need full control of the configuration.
All filters which require a reference to the AuthenticationManager
will be automatically
injected with the internal instance created by the namespace configuration (see the
introductory chapter for more on the AuthenticationManager
).
The <http>
namespace block always creates an HttpSessionContextIntegrationFilter
,
an ExceptionTranslationFilter
and a FilterSecurityInterceptor
. These are fixed
and cannot be replaced with alternatives.
The attributes on the <http>
element control some of the properties on the
core filters.
Provides versions of HttpServletRequest
security methods such as
isUserInRole()
and getPrincipal()
which are implemented by
adding a SecurityContextHolderAwareRequestFilter
bean to the stack. Defaults to "true".
Controls whether URL patterns are interpreted as ant paths (the default) or regular expressions. In practice
this sets a particular UrlMatcher
instance on the FilterChainProxy
.
Whether test URLs should be converted to lower case prior to comparing with defined path patterns. If unspecified, defaults to "true"
Indicates whether an existing session should be invalidated when a user authenticates and a new session started. If set to "none" no change will be made. "newSession" will create a new empty session. "migrateSession" will create a new session and copy the session attributes to the new session. Defaults to "migrateSession".
If enabled this will add a SessionFixationProtectionFilter
to the stack. The session fixation protection
options on namespace-created instances of AbstractProcessingFilter
will also be set appropriately.
Sets the realm name used for basic authentication (if enabled). Corresponds to the realmName
proerty on
BasicProcessingFilterEntryPoint
.
Normally the AuthenticationEntryPoint
used will be set depending on which
authentication mechanisms have been configured. This attribute allows this behaviour to be overridden
by defining a customized AuthenticationEntryPoint
bean which will start the authentication
process.
Optional attribute specifying the ID of the AccessDecisionManager
implementation which should be
used for authorizing HTTP requests. By default an AffirmativeBased
implementation is used for with
a RoleVoter
and an AuthenticatedVoter
.
Allows the access denied page to be set (the user will be redirected here if an
AccessDeniedException
is raised). Corresponds to the
errorPage
property set on the AccessDeniedHandlerImpl
which is
used by the ExceptionTranslationFilter
.
Corresponds to the observeOncePerRequest
property of
FilterSecurityInterceptor
. Defaults to "true".
Controls the eagerness with which an HTTP session is created. If not set, defaults to "ifRequired". Other options are "always" and "never".
The setting of this attribute affect the allowSessionCreation
and forceEagerSessionCreation
properties of HttpSessionContextIntegrationFilter
. allowSessionCreation
will always be true unless
this attribute is set to "never". forceEagerSessionCreation
is "false" unless it is set to "always".
So the default configuration allows session creation but does not force it. The exception is if concurrent session control is enabled,
when forceEagerSessionCreation
will be set to true, regardless of what the setting is here. Using "never" would
then cause an exception during the initialization of HttpSessionContextIntegrationFilter
.
This element is used to define the set of URL patterns that the application is interested in
and to configure how they should be handled. It is used to construct the
FilterInvocationDefinitionSource
used by the FilterSecurityInterceptor
and
to exclude particular patterns from the filter chain entirely (by setting the attribute filters="none"
).
It is also responsible for configuring a ChannelProcessingFilter
if particular URLs need to be accessed
by HTTPS, for example.
The pattern which defines the URL path. The content will depend on the path-type
attribute from the
containing http element, so will default to ant path syntax.
The HTTP Method which will be used in combination with the pattern to match an incoming request. If omitted, any method will match.
Lists the access attributes which will be stored in the FilterInvocationDefinitionSource
for the defined
URL pattern/method combination. This should be a comma-separated list of the attributes (such as role names).
Can be "http" or "https" depending on whether a particular URL pattern should be accessed over HTTP or HTTPS respectively. Alternatively
the value "any" can be used when there is no preference. If this attribute is present on any <intercept-url>
element, then a ChannelProcessingFilter
will be added to the filter stack and its additional dependencies added
to the application context. See the chapter on channel security for an
example configuration using traditional beans.
If a <port-mappings>
configuration is added, this will be used to by the SecureChannelProcessor
and InsecureChannelProcessor
beans to determine the ports used for redirecting to HTTP/HTTPS.
By default, an instance of PortMapperImpl
will be added to the configuration for use in redirecting
to secure and insecure URLs. This element can optionally be used to override the default mappings which that class defines. Each
child <port-mapping>
element defines a pair of HTTP:HTTPS ports. The default mappings are 80:443
and 8080:8443. An example of overriding these can be found in the namespace introduction.
Used to add an AuthenticationProcessingFilter
to the filter stack and an
AuthenticationProcessingFilterEntryPoint
to the application context to provide authentication
on demand. This will always take precedence over other namespace-created entry points.
If no attributes are supplied, a login page will be generated automatically at the URL "/spring-security-login"
[5]
The behaviour can be customized using the following attributes.
The URL that should be used to render the login page. Maps to the loginFormUrl
property of the AuthenticationProcessingFilterEntryPoint
. Defaults to
"/spring-security-login".
Maps to the filterProcessesUrl
property of AuthenticationProcessingFilter
.
The default value is "/j_spring_security_check".
Maps to the defaultTargetUrl
property of AuthenticationProcessingFilter
. If
not set, the default value is "/" (the application root). A user will be taken to this URL after logging in, provided they
were not asked to login while attempting to access a secured resource, when they will be taken to the originally requested URL.
If set to "true", the user will always start at the value given by default-target-url
, regardless of how
they arrived at the login page. Maps to the alwaysUseDefaultTargetUrl
property of
AuthenticationProcessingFilter
. Default value is "false".
Maps to the authenticationFailureUrl
property of AuthenticationProcessingFilter
.
Defines the URL the browser will be redirected to on login failure. Defaults to "/spring_security_login?login_error", which will
be automatically handled by the automatic login page generator, re-rendering the login page with an error message.
Adds a BasicProcessingFilter
and BasicProcessingFilterEntryPoint
to the
configuration. The latter will only be used as the configuration entry point if form-based login is not enabled.
Adds the RememberMeProcessingFilter
to the stack. This in turn will
be configured with either a TokenBasedRememberMeServices
, a PersistentTokenBasedRememberMeServices
or a user-specified bean implementing RememberMeServices
depending on the attribute settings.
If this is set, PersistentTokenBasedRememberMeServices
will be used and configured with
a JdbcTokenRepositoryImpl
instance.
Configures a PersistentTokenBasedRememberMeServices
but allows the use of a custom
PersistentTokenRepository
bean.
Allows complete control of the RememberMeServices
implementation that will be used
by the filter. The value should be the Id of a bean in the application context which implements this interface.
Configures a PersistentTokenBasedRememberMeServices
but allows the use of a custom
PersistentTokenRepository
bean.
Maps to the "key" property of AbstractRememberMeServices
. Should be set to a unique
value to ensure that remember-me cookies are only valid within the one application [6].
Maps to the tokenValiditySeconds
property of AbstractRememberMeServices
. Specifies the period
in seconds for which the remember-me cookie should be valid. By default it will be valid for 14 days.
The remember-me services implementations require access to a UserDetailsService
, so there has to be
one defined in the application context. If there is only one, it will be selected and used automatically by the namespace configuration.
If there are multiple instances, you can specify a bean Id explicitly using this attribute.
Adds support for concurrent session control, allowing limits to be placed on the number of active sessions a user can have.
A ConcurrentSessionFilter
will be created, along with a ConcurrentSessionControllerImpl
and an instance of SessionRegistry
(a SessionRegistryImpl
instance unless the user
wishes to use a custom bean). The controller is registered with the namespace's AuthenticationManager
(ProviderManager
). Other namespace-created beans which require a reference to the SessionRegistry
will automatically have it injected.
Note that the forceEagerSessionCreation
of HttpSessionContextIntegrationFilter
will
be set to true
if concurrent session control is in use.
Maps to the maximumSessions
property of ConcurrentSessionControllerImpl
.
The URL a user will be redirected to if they attempt to use a session which has been "expired" by
the concurrent session controller because the user has exceeded the number of allowed sessions and has logged
in again elsewhere. Should be set unless exception-if-maximum-exceeded
is set.
If no value is supplied, an expiry message will just be written directly back to the response.
If set to "true" a ConcurrentLoginException
should be raised when a user
attempts to exceed the maximum allowed number of sessions. The default behaviour is to expire the original session.
The user can supply their own SessionRegistry
implementation using the
session-registry-ref
attribute. The other concurrent session control beans will be wired
up to use it.
It can also be useful to have a reference to the internal session registry for use in your own
beans or an admin interface. You can expose the interal bean using the session-registry-alias
attribute, giving it a name that you can use elsewhere in your configuration.
Adds an AnonymousProcessingFilter
to the stack and an AnonymousAuthenticationProvider
.
Required if you are using the IS_AUTHENTICATED_ANONYMOUSLY
attribute.
Adds support for X.509 authentication. An X509PreAuthenticatedProcessingFilter
will be
added to the stack and a PreAuthenticatedProcessingFilterEntryPoint
bean will be created. The
latter will only be used if no other authentication mechanisms are in use (it's only functionality is to return an HTTP
403 error code). A PreAuthenticatedAuthenticationProvider
will also be created which delegates the
loading of user authorities to a UserDetailsService
.
Defines a regular expression which will be used to extract the username from the certificate (for use with the
UserDetailsService
).
Similar to <form-login>
and has the same attributes. The default value for login-processing-url
is "/j_spring_openid_security_check". An OpenIDAuthenticationProcessingFilter
and OpenIDAuthenticationProvider
will be registered. The latter requires a reference to a UserDetailsService
. Again, this can be
specified by Id, using the user-service-ref
attribute, or will be located automatically in the application context.
Adds a LogoutFilter
to the filter stack. This is configured
with a SecurityContextLogoutHandler
.
The URL which will cause a logout (i.e. which will be processed by the filter). Defaults to "/j_spring_security_logout".
The destination URL which the user will be taken to after logging out. Defaults to "/".
If you are using the namespace, an AuthenticationManager
is
automatically registered and will be used by all the namespace-created beans which need to reference it.
The bean is an instance of Spring Security's ProviderManager
class, which needs to be
configured with a list of one or more AuthenticationProvider
instances.
These can either be created using syntax elements provided by the namespace, or they can be
standard bean definitions, marked for addition to the list using the
custom-authentication-provider
element.
This element is basically a shorthand syntax for configuring a DaoAuthenticationProvider
.
DaoAuthenticationProvider
loads user information from a UserDetailsService
and
compares the username/password combination with the values supplied at login. The UserDetailsService
instance
can be defined either by using an available namespace element (jdbc-user-service
or by using the user-service-ref
attribute to point to a bean defined elsewhere in the application context). You can find examples of these variations in the
namespace introduction.
If you have written your own AuthenticationProvider
implementation (or want
to configure one of Spring Security's own implementations as a traditional bean for some reason, then
you can use the following syntax to add it to the internal ProviderManager
's list:
<bean id="myAuthenticationProvider" class="com.something.MyAuthenticationProvider"> <security:custom-authentication-provider /> </bean>
Since the AuthenticationManager
will be automatically registered in the application
context, this element is entirely optional. It allows you to define an alias name for the internal instance for use
in your own configuration and also to supply a link to a ConcurrentSessionController
if you are configuring concurrent session control yourself rather than through the namespace (a rare requirement).
Its use is described in the namespace introduction.
This element is the primary means of adding support for securing methods on Spring Security beans. Methods can be secured by the use of annotations (defined at the interface or class level) or by defining a set of pointcuts as child elements, using AspectJ syntax.
Method security uses the same AccessDecisionManager
configuration as web security,
but this can be overridden as explained above Section B.1.1.7, “access-decision-manager-ref
”, using the same
attribute.
Setting these to "true" will enable support for Spring Security's own @Secured
annotations and
JSR-250 annotations, respectively. They are both disabled by default. Use of JSR-250 annotations also adds a
Jsr250Voter
to the AccessDecisionManager
, so you need to
make sure you do this if you are using a custom implementation and want to use these annotations.
Rather than defining security attributes on an individual method or class basis using the
@Secured
annotation, you can define cross-cutting security constraints across whole
sets of methods and interfaces in your service layer using the <protect-pointcut>
element. This has two attributes:
expression
- the pointcut expression
access
- the security attributes which apply
You can find an example in the namespace introduction.
LDAP is covered in some details in its own chapter. We will expand on that here with some explanation of how the namespace options map to Spring beans. The LDAP implementation uses Spring LDAP extensively, so some familiarity with that project's API may be useful.
This element sets up a Spring LDAP ContextSource
for use by the
other LDAP beans, defining the location of the LDAP server and other information (such as a username
and password, if it doesn't allow anonymous access) for connecting to it. It can also be used to
create an embedded server for testing.
Details of the syntax for both options are covered in the LDAP chapter.
The actual ContextSource
implementation is
DefaultSpringSecurityContextSource
which extends Spring LDAP's
LdapContextSource
class. The manager-dn
and manager-password
attributes map to the latter's userDn
and password
properties respectively.
If you only have one server defined in your application context, the other LDAP namespace-defined beans
will use it automatically. Otherwise, you can give the element an "id" attribute and refer to it from other
namespace beans using the server-ref
attribute. This is actually the bean Id of the
ContextSource
instance, if you want to use it in other traditional Spring beans.
This element is shorthand for the creation of an LdapAuthenticationProvider
instance.
By default this will be configured with a BindAuthenticator
instance and a
DefaultAuthoritiesPopulator
.
If your users are at a fixed location in the directory (i.e. you can work out the DN
directly from the username without doing a directory search), you can use this attribute
to map directly to the DN. It maps directly to the userDnPatterns
property of AbstractLdapAuthenticator
.
If you need to perform a search to locate the user in the directory, then you
can set these attributes to control the search. The BindAuthenticator
will be configured
with a FilterBasedLdapUserSearch
and the attribute values map directly to the first two
arguments of that bean's constructor. If these attributes aren't set and no user-dn-pattern
has been supplied as an alternative, then the default search values of user-search-filter="(uid={0})"
and user-search-base=""
will be used.
The value of group-search-base
is mapped to the groupSearchBase
constructor argument
of DefaultAuthoritiesPopulator
and defaults to "ou=groups". The default filter value is
"(uniqueMember={0})", which assumes that the entry is of type "groupOfUniqueNames". group-role-attribute
maps to the groupRoleAttribute
attribute and defaults to "cn". Similarly role-prefix
maps to rolePrefix
and defaults to "ROLE_".
This is used as child element to <ldap-provider>
and switches
the authentication strategy from BindAuthenticator
to
PasswordComparisonAuthenticator
. This can optionally be supplied with a
hash
attribute or with a child <password-encoder>
element to hash the password before submitting it to the directory for comparison.
[4] See the
introductory chapter for how to set up the mapping from
your web.xml
[5] This feature is really just provided for convenience and is not intended for production (where a
view technology will have been chosen and can be used to render a customized login page). The class
DefaultLoginPageGeneratingFilter
is responsible for rendering the login
page and will provide login forms for both normal form login and/or OpenID if required.
[6] This doesn't affect
the use of PersistentTokenBasedRememberMeServices
, where the tokens are stored on the server side.