| java.lang.Object
 javax.security.auth.login.LoginContext
| LoginContext | | public class LoginContext (Code) | | The LoginContext class describes the basic methods used
to authenticate Subjects and provides a way to develop an
application independent of the underlying authentication technology.
A Configuration specifies the authentication technology, or
LoginModule, to be used with a particular application.
Different LoginModules can be plugged in under an application
without requiring any modifications to the application itself.
In addition to supporting pluggable authentication, this class
also supports the notion of stacked authentication.
Applications may be configured to use more than one
LoginModule. For example, one could
configure both a Kerberos LoginModule and a smart card
LoginModule under an application.
A typical caller instantiates a LoginContext with
a name and a CallbackHandler.
LoginContext uses the name as the index into a
Configuration to determine which LoginModules should be used,
and which ones must succeed in order for the overall authentication to
succeed. The CallbackHandler is passed to the underlying
LoginModules so they may communicate and interact with users
(prompting for a username and password via a graphical user interface,
for example).
Once the caller has instantiated a LoginContext,
it invokes the login method to authenticate
a Subject. The login method invokes
the configured modules to perform their respective types of authentication
(username/password, smart card pin verification, etc.).
Note that the LoginModules will not attempt authentication retries nor
introduce delays if the authentication fails.
Such tasks belong to the LoginContext caller.
If the login method returns without
throwing an exception, then the overall authentication succeeded.
The caller can then retrieve
the newly authenticated Subject by invoking the
getSubject method. Principals and Credentials associated
with the Subject may be retrieved by invoking the Subject's
respective getPrincipals, getPublicCredentials,
and getPrivateCredentials methods.
To logout the Subject, the caller calls
the logout method. As with the login
method, this logout method invokes the logout
method for the configured modules.
A LoginContext should not be used to authenticate
more than one Subject. A separate LoginContext
should be used to authenticate each different Subject.
The following documentation applies to all LoginContext constructors:
-
Subject
- If the constructor has a Subject
input parameter, the LoginContext uses the caller-specified
Subject object.
- If the caller specifies a
null Subject
and a null value is permitted,
the LoginContext instantiates a new Subject.
- If the constructor does not have a Subject
input parameter, the LoginContext instantiates a new Subject.
-
Configuration
- If the constructor has a Configuration
input parameter and the caller specifies a non-null Configuration,
the LoginContext uses the caller-specified Configuration.
If the constructor does not have a Configuration
input parameter, or if the caller specifies a null
Configuration object, the constructor uses the following call to
get the installed Configuration:
config = Configuration.getConfiguration();
For both cases,
the name argument given to the constructor is passed to the
Configuration.getAppConfigurationEntry method.
If the Configuration has no entries for the specified name,
then the LoginContext calls
getAppConfigurationEntry with the name, "other"
(the default entry name). If there is no entry for "other",
then a LoginException is thrown.
- When LoginContext uses the installed Configuration, the caller
requires the createLoginContext.name and possibly
createLoginContext.other AuthPermissions. Furthermore, the
LoginContext will invoke configured modules from within an
AccessController.doPrivileged call so that modules that
perform security-sensitive tasks (such as connecting to remote hosts,
and updating the Subject) will require the respective permissions, but
the callers of the LoginContext will not require those permissions.
- When LoginContext uses a caller-specified Configuration, the caller
does not require any createLoginContext AuthPermission. The LoginContext
saves the
AccessControlContext for the caller,
and invokes the configured modules from within an
AccessController.doPrivileged call constrained by that context.
This means the caller context (stored when the LoginContext was created)
must have sufficient permissions to perform any security-sensitive tasks
that the modules may perform.
-
CallbackHandler
- If the constructor has a CallbackHandler
input parameter, the LoginContext uses the caller-specified
CallbackHandler object.
- If the constructor does not have a CallbackHandler
input parameter, or if the caller specifies a
null
CallbackHandler object (and a null value is permitted),
the LoginContext queries the
auth.login.defaultCallbackHandler security property
for the fully qualified class name of a default handler implementation.
If the security property is not set,
then the underlying modules will not have a
CallbackHandler for use in communicating
with users. The caller thus assumes that the configured
modules have alternative means for authenticating the user.
- When the LoginContext uses the installed Configuration (instead of
a caller-specified Configuration, see above),
then this LoginContext must wrap any
caller-specified or default CallbackHandler implementation
in a new CallbackHandler implementation
whose
handle method implementation invokes the
specified CallbackHandler's handle method in a
java.security.AccessController.doPrivileged call
constrained by the caller's current AccessControlContext.
Note that Security Properties
(such as auth.login.defaultCallbackHandler)
can be set programmatically via the
java.security.Security class,
or statically in the Java security properties file located in the
file named <JAVA_HOME>/lib/security/java.security.
<JAVA_HOME> refers to the value of the java.home system property,
and specifies the directory where the JRE is installed.
version:
1.107, 05/05/07
See Also: java.security.Security
See Also: javax.security.auth.AuthPermission
See Also: javax.security.auth.Subject
See Also: javax.security.auth.callback.CallbackHandler
See Also: javax.security.auth.login.Configuration
See Also: javax.security.auth.spi.LoginModule |
| Constructor Summary | |
| public | LoginContext(String name)
Instantiate a new LoginContext object with a name. | | public | LoginContext(String name, Subject subject)
Instantiate a new LoginContext object with a name
and a Subject object.
Parameters:
name - the name used as the index into theConfiguration. | | public | LoginContext(String name, CallbackHandler callbackHandler)
Instantiate a new LoginContext object with a name
and a CallbackHandler object.
Parameters:
name - the name used as the index into theConfiguration. | | public | LoginContext(String name, Subject subject, CallbackHandler callbackHandler)
Instantiate a new LoginContext object with a name,
a Subject to be authenticated, and a
CallbackHandler object.
Parameters:
name - the name used as the index into theConfiguration. | | public | LoginContext(String name, Subject subject, CallbackHandler callbackHandler, Configuration config)
Instantiate a new LoginContext object with a name,
a Subject to be authenticated,
a CallbackHandler object, and a login
Configuration.
Parameters:
name - the name used as the index into the caller-specifiedConfiguration. |
| Method Summary | |
| public Subject | getSubject()
Return the authenticated Subject.
the authenticated Subject. | | public void | login()
Perform the authentication.
This method invokes the login method for each
LoginModule configured for the name specified to the
LoginContext constructor, as determined by the login
Configuration. | | public void | logout()
Logout the Subject.
This method invokes the logout method for each
LoginModule configured for this LoginContext.
Each LoginModule performs its respective logout procedure
which may include removing/destroying
Principal and Credential information
from the Subject and state cleanup.
Note that this method invokes all LoginModules configured for the
application regardless of their respective
Configuration flag parameters. |
| LoginContext | | public LoginContext(String name) throws LoginException(Code) | | Instantiate a new LoginContext object with a name.
Parameters:
name - the name used as the index into theConfiguration.
exception:
LoginException - if the caller-specified namedoes not appear in the Configurationand there is no Configuration entryfor "other", or if theauth.login.defaultCallbackHandlersecurity property was set, but the implementationclass could not be loaded.
exception:
SecurityException - if a SecurityManager is set andthe caller does not haveAuthPermission("createLoginContext.name"),or if a configuration entry for name does not exist andthe caller does not additionally haveAuthPermission("createLoginContext.other")
|
| LoginContext | | public LoginContext(String name, Subject subject) throws LoginException(Code) | | Instantiate a new LoginContext object with a name
and a Subject object.
Parameters:
name - the name used as the index into theConfiguration.
Parameters:
subject - the Subject to authenticate.
exception:
LoginException - if the caller-specified namedoes not appear in the Configurationand there is no Configuration entryfor "other", if the caller-specified subjectis null, or if theauth.login.defaultCallbackHandlersecurity property was set, but the implementationclass could not be loaded.
exception:
SecurityException - if a SecurityManager is set andthe caller does not haveAuthPermission("createLoginContext.name"),or if a configuration entry for name does not exist andthe caller does not additionally haveAuthPermission("createLoginContext.other")
|
| LoginContext | | public LoginContext(String name, CallbackHandler callbackHandler) throws LoginException(Code) | | Instantiate a new LoginContext object with a name
and a CallbackHandler object.
Parameters:
name - the name used as the index into theConfiguration.
Parameters:
callbackHandler - the CallbackHandler object used byLoginModules to communicate with the user.
exception:
LoginException - if the caller-specified namedoes not appear in the Configurationand there is no Configuration entryfor "other", or if the caller-specifiedcallbackHandler is null.
exception:
SecurityException - if a SecurityManager is set andthe caller does not haveAuthPermission("createLoginContext.name"),or if a configuration entry for name does not exist andthe caller does not additionally haveAuthPermission("createLoginContext.other")
|
| LoginContext | | public LoginContext(String name, Subject subject, CallbackHandler callbackHandler) throws LoginException(Code) | | Instantiate a new LoginContext object with a name,
a Subject to be authenticated, and a
CallbackHandler object.
Parameters:
name - the name used as the index into theConfiguration.
Parameters:
subject - the Subject to authenticate.
Parameters:
callbackHandler - the CallbackHandler object used byLoginModules to communicate with the user.
exception:
LoginException - if the caller-specified namedoes not appear in the Configurationand there is no Configuration entryfor "other", or if the caller-specifiedsubject is null,or if the caller-specifiedcallbackHandler is null.
exception:
SecurityException - if a SecurityManager is set andthe caller does not haveAuthPermission("createLoginContext.name"),or if a configuration entry for name does not exist andthe caller does not additionally haveAuthPermission("createLoginContext.other")
|
| LoginContext | | public LoginContext(String name, Subject subject, CallbackHandler callbackHandler, Configuration config) throws LoginException(Code) | | Instantiate a new LoginContext object with a name,
a Subject to be authenticated,
a CallbackHandler object, and a login
Configuration.
Parameters:
name - the name used as the index into the caller-specifiedConfiguration.
Parameters:
subject - the Subject to authenticate,or null.
Parameters:
callbackHandler - the CallbackHandler object used byLoginModules to communicate with the user, or null.
Parameters:
config - the Configuration that lists thelogin modules to be called to perform the authentication,or null.
exception:
LoginException - if the caller-specified namedoes not appear in the Configurationand there is no Configuration entryfor "other".
exception:
SecurityException - if a SecurityManager is set,config is null,and either the caller does not haveAuthPermission("createLoginContext.name"),or if a configuration entry for name does not exist andthe caller does not additionally haveAuthPermission("createLoginContext.other")
since:
1.5
|
| getSubject | | public Subject getSubject()(Code) | | Return the authenticated Subject.
the authenticated Subject. If the caller specified aSubject to this LoginContext's constructor,this method returns the caller-specified Subject.If a Subject was not specified and authentication succeeds,this method returns the Subject instantiated and used forauthentication by this LoginContext.If a Subject was not specified, and authentication fails orhas not been attempted, this method returns null. |
| login | | public void login() throws LoginException(Code) | | Perform the authentication.
This method invokes the login method for each
LoginModule configured for the name specified to the
LoginContext constructor, as determined by the login
Configuration. Each LoginModule
then performs its respective type of authentication
(username/password, smart card pin verification, etc.).
This method completes a 2-phase authentication process by
calling each configured LoginModule's commit method
if the overall authentication succeeded (the relevant REQUIRED,
REQUISITE, SUFFICIENT, and OPTIONAL LoginModules succeeded),
or by calling each configured LoginModule's abort method
if the overall authentication failed. If authentication succeeded,
each successful LoginModule's commit method associates
the relevant Principals and Credentials with the Subject.
If authentication failed, each LoginModule's abort method
removes/destroys any previously stored state.
If the commit phase of the authentication process
fails, then the overall authentication fails and this method
invokes the abort method for each configured
LoginModule.
If the abort phase
fails for any reason, then this method propagates the
original exception thrown either during the login phase
or the commit phase. In either case, the overall
authentication fails.
In the case where multiple LoginModules fail,
this method propagates the exception raised by the first
LoginModule which failed.
Note that if this method enters the abort phase
(either the login or commit phase failed),
this method invokes all LoginModules configured for the
application regardless of their respective Configuration
flag parameters. Essentially this means that Requisite
and Sufficient semantics are ignored during the
abort phase. This guarantees that proper cleanup
and state restoration can take place.
exception:
LoginException - if the authentication fails. |
| logout | | public void logout() throws LoginException(Code) | | Logout the Subject.
This method invokes the logout method for each
LoginModule configured for this LoginContext.
Each LoginModule performs its respective logout procedure
which may include removing/destroying
Principal and Credential information
from the Subject and state cleanup.
Note that this method invokes all LoginModules configured for the
application regardless of their respective
Configuration flag parameters. Essentially this means
that Requisite and Sufficient semantics are
ignored for this method. This guarantees that proper cleanup
and state restoration can take place.
exception:
LoginException - if the logout fails. |
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