The Security Namespace 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 namespace is written in RELAX NG Compact format and later converted into
an XSD schema. If you are familiar with this format, you may wish to examine the schema file directly.Web Application Security - the <http> Element If you use an <http> element within your application, a
FilterChainProxy bean named "springSecurityFilterChain" is
created and the configuration within the element is used to build a filter chain within
FilterChainProxy. As of Spring Security 3.1, additional
http elements can be used to add extra filter chains See the introductory chapter for how to set
up the mapping from your web.xml. Some core filters are always created in a filter chain and others will be
added to the stack depending on the attributes and 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). Each <http> namespace block always creates an
SecurityContextPersistenceFilter, an
ExceptionTranslationFilter and a
FilterSecurityInterceptor. These are fixed and cannot be replaced
with alternatives. <http> Attributes The attributes on the <http> element control some of the
properties on the core filters. patternDefining a pattern for the http element controls the
requests which will be filtered through the list of filters which it defines.
The interpretation is dependent on the configured request-matcher. If no pattern is defined,
all requests will be matched, so the most specific patterns should be declared
first. securityA request pattern can be mapped to an empty filter chain, by setting this
attribute to none. No security will be applied and none of
Spring Security's features will be available. servlet-api-provision 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".jaas-api-provisionIf available, runs the request as the Subject acquired from
the JaasAuthenticationToken which is implemented by
adding a JaasApiIntegrationFilter bean to the stack.
Defaults to "false".request-matcher Defines the RequestMatcher strategy used in
the FilterChainProxy and the beans created by the
intercept-url to match incoming requests. Options are
currently ant, regex and
ciRegex, for ant, regular-expression and case-insensitive
regular-expression repsectively. A separate instance is created for each
intercept-url element using its pattern
and method attributes (see below). Ant paths are matched
using an AntPathRequestMatcher and regular expressions
are matched using a RegexRequestMatcher. See the Javadoc
for these classes for more details on exactly how the matching is preformed. Ant
paths are the default strategy.realm Sets the realm name used for basic authentication (if enabled). Corresponds
to the realmName property on
BasicAuthenticationEntryPoint. entry-point-ref 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. security-context-repository-ref Allows injection of a custom
SecurityContextRepository into the
SecurityContextPersistenceFilter. access-decision-manager-ref 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. access-denied-page Deprecated in favour of the access-denied-handler child
element. once-per-request Corresponds to the observeOncePerRequest property of
FilterSecurityInterceptor. Defaults to "true". create-session 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. use-expressionsEnables EL-expressions in the access attribute, as
described in the chapter on expression-based
access-control. disable-url-rewritingPrevents session IDs from being appended to URLs in the application. Clients
must use cookies if this attribute is set to true. <access-denied-handler> This element allows you to set the errorPage property for the
default AccessDeniedHandler used by the
ExceptionTranslationFilter, (using the
error-page attribute, or to supply your own implementation using
the ref attribute. This is discussed in more detail in the
section on the
ExceptionTranslationFilter.The <intercept-url> Element 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 FilterInvocationSecurityMetadataSource used by
the FilterSecurityInterceptor. It is also responsible for
configuring a ChannelAuthenticationFilter if particular URLs
need to be accessed by HTTPS, for example. When matching the specified patterns
against an incoming request, the matching is done in the order in which the elements
are declared. So the most specific matches patterns should come first and the most
general should come last.pattern The pattern which defines the URL path. The content will depend on the
request-matcher attribute from the containing http element,
so will default to ant path syntax. method The HTTP Method which will be used in combination with the pattern to match
an incoming request. If omitted, any method will match. If an identical pattern
is specified with and without a method, the method-specific match will take
precedence.access Lists the access attributes which will be stored in the
FilterInvocationSecurityMetadataSource for the
defined URL pattern/method combination. This should be a comma-separated list of
the security configuration attributes (such as role names). requires-channel 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
ChannelAuthenticationFilter will be added to the filter
stack and its additional dependencies added to the application
context. 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. filtersCan only take the value none. This will cause any matching
request to bypass the Spring Security filter chain entirely. None of the rest of
the <http> configuration will have any effect on the
request and there will be no security context available for its duration. Access
to secured methods during the request will fail.The <port-mappings> Element 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. The <form-login> Element Used to add an UsernamePasswordAuthenticationFilter to the
filter stack and an LoginUrlAuthenticationEntryPoint 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" 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. The behaviour can be customized using the following attributes. login-page The URL that should be used to render the login page. Maps to the
loginFormUrl property of the
LoginUrlAuthenticationEntryPoint. Defaults to
"/spring_security_login". login-processing-url Maps to the filterProcessesUrl property of
UsernamePasswordAuthenticationFilter. The default value
is "/j_spring_security_check". default-target-urlMaps to the defaultTargetUrl property of
UsernamePasswordAuthenticationFilter. 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. always-use-default-target 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
UsernamePasswordAuthenticationFilter. Default value is
"false". authentication-failure-url Maps to the authenticationFailureUrl property of
UsernamePasswordAuthenticationFilter. 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. authentication-success-handler-refThis can be used as an alternative to default-target-url
and always-use-default-target, giving you full control over
the navigation flow after a successful authentication. The value should be the
name of an AuthenticationSuccessHandler bean in
the application context. By default, an imlementation of
SavedRequestAwareAuthenticationSuccessHandler is used and
injected with the default-target-url.authentication-failure-handler-refCan be used as an alternative to
authentication-failure-url, giving you full control over the
navigation flow after an authentication failure. The value should be he name of
an AuthenticationFailureHandler bean in the
application context. The <http-basic> Element Adds a BasicAuthenticationFilter and
BasicAuthenticationEntryPoint to the configuration. The
latter will only be used as the configuration entry point if form-based login is not
enabled. The <remember-me> Element Adds the RememberMeAuthenticationFilter 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. data-source-ref If this is set, PersistentTokenBasedRememberMeServices
will be used and configured with a
JdbcTokenRepositoryImpl instance. services-ref 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. Should also implement
LogoutHandler if a logout filter is in use.token-repository-ref Configures a PersistentTokenBasedRememberMeServices
but allows the use of a custom
PersistentTokenRepository bean. The key AttributeMaps 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 This doesn't affect the use of
PersistentTokenBasedRememberMeServices, where the
tokens are stored on the server side.. token-validity-seconds 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. user-service-ref 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. authentication-success-handler-refSets the authenticationSuccessHandler property on the
RememberMeAuthenticationFilter if custom navigation is required.
The value should be the name of a AuthenticationSuccessHandler
bean in the application context. The <session-management> ElementSession-management related functionality is implemented by the addition of a
SessionManagementFilter to the filter stack.session-fixation-protection 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 session fixation protection is enabled, the
SessionManagementFilter is inected with a appropriately
configured DefaultSessionAuthenticationStrategy. See the
Javadoc for this class for more details. The <concurrency-control> Element 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, and a
ConcurrentSessionControlStrategy will be used with the
SessionManagementFilter. If a form-login
element has been declared, the strategy object will also be injected into the
created authentication filter. An instance of
SessionRegistry (a
SessionRegistryImpl instance unless the user wishes to use a
custom bean) will be created for use by the strategy.The max-sessions attributeMaps to the maximumSessions property of
ConcurrentSessionControlStrategy.The expired-url attribute 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. The error-if-maximum-exceeded attributeIf set to "true" a
SessionAuthenticationException will be raised
when a user attempts to exceed the maximum allowed number of sessions. The
default behaviour is to expire the original session. The session-registry-alias and
session-registry-ref attributes 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. The <anonymous> Element Adds an AnonymousAuthenticationFilter to the stack and an
AnonymousAuthenticationProvider. Required if you are using
the IS_AUTHENTICATED_ANONYMOUSLY attribute. The <x509> Element Adds support for X.509 authentication. An
X509AuthenticationFilter will be added to the stack and an
Http403ForbiddenEntryPoint 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. The subject-principal-regex attribute Defines a regular expression which will be used to extract the username from
the certificate (for use with the
UserDetailsService). The user-service-ref attribute Allows a specific UserDetailsService to be
used with X.509 in the case where multiple instances are configured. If not set,
an attempt will be made to locate a suitable instance automatically and use
that. The <openid-login> Element Similar to <form-login> and has the same attributes. The
default value for login-processing-url is
"/j_spring_openid_security_check". An
OpenIDAuthenticationFilter 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. The <attribute-exchange> ElementThe attribute-exchange element defines the list of
attributes which should be requested from the identity provider. More than one
can be used, in which case each must have an identifier-match
attribute, containing a regular expression which is matched against the supplied
OpenID identifer. This allows different attribute lists to be fetched from
different providers (Google, Yahoo etc).The <logout> Element Adds a LogoutFilter to the filter stack. This is
configured with a SecurityContextLogoutHandler. The logout-url attribute The URL which will cause a logout (i.e. which will be processed by the
filter). Defaults to "/j_spring_security_logout". The logout-success-url attribute The destination URL which the user will be taken to after logging out.
Defaults to "/". The success-handler-ref attributeMay be used to supply an instance of LogoutSuccessHandler
which will be invoked to control the navigation after logging out.
The invalidate-session attribute Maps to the invalidateHttpSession of the
SecurityContextLogoutHandler. Defaults to "true", so the
session will be invalidated on logout.The delete-cookies attributeA comma-separated list of the names of cookies which should be deleted when the user logs out.
The <custom-filter> ElementThis element is used to add a filter to the filter chain. It doesn't create any
additional beans but is used to select a bean of type
javax.servlet.Filter which is already defined in the
appllication context and add that at a particular position in the filter chain
maintained by Spring Security. Full details can be found in the namespace
chapter.The <request-cache> ElementSets the RequestCache instance which will be used
by the ExceptionTranslationFilter to store request
information before invoking an
AuthenticationEntryPoint. The <http-firewall> ElementThis is a top-level element which can be used to inject a custom implementation of
HttpFirewall into the
FilterChainProxy created by the namespace. The default
implementation should be suitable for most applications.Authentication Services Before Spring Security 3.0, an AuthenticationManager
was automatically registered internally. Now you must register one explicitly using the
<authentication-manager> element. This creates 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
authentication-provider element. The <authentication-manager> Element Every Spring Security application which uses the namespace must have include this
element somewhere. It is responsible for registering the
AuthenticationManager which provides authentication
services to the application. It also allows you to define an alias name for the
internal instance for use in your own configuration. Its use is described in the
namespace introduction. All elements
which create AuthenticationProvider instances should
be children of this element. The element also exposes an erase-credentials attribute which
maps to the eraseCredentialsAfterAuthentication property of the
ProviderManager. This is discussed in the Core Services chapter.The <authentication-provider> Element Unless used with a ref attribute, this element is
shorthand 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. The <password-encoder> ElementAuthentication providers can optionally be configured to use a password
encoder as described in the namespace introduction. This will result in the bean being injected
with the appropriate PasswordEncoder
instance, potentially with an accompanying
SaltSource bean to provide salt values for
hashing. Using <authentication-provider> to refer to an
AuthenticationProvider Bean 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:
]]>Method SecurityThe <global-method-security> Element 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 , using the same attribute. The secured-annotations and
jsr250-annotations Attributes 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. The mode AttributeThis attribute can be set to aspectj to specify that AspectJ
should be used instead of the default Spring AOP. Secured methods must be woven
with the AnnotationSecurityAspect from the
spring-security-aspects module. Securing Methods using <protect-pointcut> 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 expressionaccess - the security attributes which apply You can find an example in the namespace introduction. The <after-invocation-provider> Element This element can be used to decorate an
AfterInvocationProvider for use by the security
interceptor maintained by the <global-method-security>
namespace. You can define zero or more of these within the
global-method-security element, each with a
ref attribute pointing to an
AfterInvocationProvider bean instance within your
application context. LDAP Namespace Options 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. Defining the LDAP Server using the <ldap-server>
Element 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. The <ldap-provider> Element This element is shorthand for the creation of an
LdapAuthenticationProvider instance. By default this will
be configured with a BindAuthenticator instance and a
DefaultAuthoritiesPopulator. As with all namespace
authentication providers, it must be included as a child of the
authentication-provider element.The user-dn-pattern Attribute 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. The user-search-base and
user-search-filter Attributes 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. group-search-filter,
group-search-base,
group-role-attribute and role-prefix
Attributes 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_". The <password-compare> Element 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. The <ldap-user-service> Element This element configures an LDAP
UserDetailsService. The class used is
LdapUserDetailsService which is a combination of a
FilterBasedLdapUserSearch and a
DefaultAuthoritiesPopulator. The attributes it supports
have the same usage as in <ldap-provider>.