All Known Implementing Classes:

IPAuthentication, LDAPAuthentication, OidcAuthentication, OidcAuthenticationBean, OrcidAuthentication, OrcidAuthenticationBean, PasswordAuthentication, ShibAuthentication, X509Authentication
```
public interface AuthenticationMethod
```
Implement this interface to participate in the stackable authentication mechanism. See the AuthenticationManager class for details about configuring authentication handlers.
Each authentication method provides a way to map "credentials" supplied by the client into a DSpace e-person. "Authentication" is when the credentials are compared against some sort of registry or other test of authenticity.
The DSpace instance may configure many authentication methods, in a "stack". The same credentials are passed to each method in turn until one accepts them, so each method need only attempt to interpret and validate the credentials and fail gracefully if they are not appropriate for it. The next method in the stack is then called.

Version:

$Revision$

Author:

Larry Stone

See Also:

AuthenticationService

Field Summary

Fields
Modifier and Type	Field	Description
`static int`	`BAD_ARGS`	User or password is not appropriate for this method.
`static int`	`BAD_CREDENTIALS`	User exists, but credentials (e.g. passwd) don't match.
`static int`	`CERT_REQUIRED`	Not allowed to login this way without X.509 certificate.
`static int`	`NO_SUCH_USER`	User not found using this method.
`static int`	`SUCCESS`	Authenticated OK, EPerson has been set.

Method Summary

All Methods Instance Methods Abstract Methods Default Methods
Modifier and Type	Method	Description
`boolean`	`allowSetPassword(Context context, javax.servlet.http.HttpServletRequest request, String username)`	Should (or can) we allow the user to change their password.
`default boolean`	`areSpecialGroupsApplicable(Context context, javax.servlet.http.HttpServletRequest request)`	Returns true if the special groups returned by `getSpecialGroups(Context, HttpServletRequest)` should be implicitly be added to the groups related to the current user.
`int`	`authenticate(Context context, String username, String password, String realm, javax.servlet.http.HttpServletRequest request)`	Authenticate the given or implicit credentials.
`boolean`	`canChangePassword(Context context, EPerson ePerson, String currentPassword)`	Check if the given current password is valid to change the password of the given ePerson
`boolean`	`canSelfRegister(Context context, javax.servlet.http.HttpServletRequest request, String username)`	Predicate, whether to allow new EPerson to be created.
`String`	`getName()`	Returns a short name that uniquely identifies this authentication method
`List<Group>`	`getSpecialGroups(Context context, javax.servlet.http.HttpServletRequest request)`	Get list of extra groups that user implicitly belongs to.
`void`	`initEPerson(Context context, javax.servlet.http.HttpServletRequest request, EPerson eperson)`	Initialize a new EPerson record for a self-registered new user.
`boolean`	`isImplicit()`	Predicate, is this an implicit authentication method.
`boolean`	`isUsed(Context context, javax.servlet.http.HttpServletRequest request)`	Get whether the authentication method is being used.
`String`	`loginPageURL(Context context, javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response)`	Get an external login page to which to redirect.

- Field Detail
  - SUCCESS
```
static final int SUCCESS
```
    Authenticated OK, EPerson has been set.
    
    See Also:
    
    Constant Field Values
  - BAD_CREDENTIALS
```
static final int BAD_CREDENTIALS
```
    User exists, but credentials (e.g. passwd) don't match.
    
    See Also:
    
    Constant Field Values
  - CERT_REQUIRED
```
static final int CERT_REQUIRED
```
    Not allowed to login this way without X.509 certificate.
    
    See Also:
    
    Constant Field Values
  - NO_SUCH_USER
```
static final int NO_SUCH_USER
```
    User not found using this method.
    
    See Also:
    
    Constant Field Values
  - BAD_ARGS
```
static final int BAD_ARGS
```
    User or password is not appropriate for this method.
    
    See Also:
    
    Constant Field Values
- Method Detail
  - canSelfRegister
```
boolean canSelfRegister(Context context,
                        javax.servlet.http.HttpServletRequest request,
                        String username)
                 throws SQLException
```
    Predicate, whether to allow new EPerson to be created. The answer determines whether a new user is created when the credentials describe a valid entity but there is no corresponding EPerson in DSpace yet. The EPerson is only created if authentication succeeds.
    
    Parameters:
    
    context - DSpace context
    
    request - HTTP request, in case it's needed. May be null.
    
    username - Username, if available. May be null.
    
    Returns:
    
    true if new ePerson should be created.
    
    Throws:
    
    SQLException - if database error
  - initEPerson
```
void initEPerson(Context context,
                 javax.servlet.http.HttpServletRequest request,
                 EPerson eperson)
          throws SQLException
```
    Initialize a new EPerson record for a self-registered new user. Set any data in the EPerson that is specific to this authentication method.
    
    Parameters:
    
    context - DSpace context
    
    request - HTTP request, in case it's needed. May be null.
    
    eperson - newly created EPerson record - email + information from the registration form will have been filled out.
    
    Throws:
    
    SQLException - if database error
  - allowSetPassword
```
boolean allowSetPassword(Context context,
                         javax.servlet.http.HttpServletRequest request,
                         String username)
                  throws SQLException
```
    Should (or can) we allow the user to change their password. Note that this means the password stored in the EPerson record, so if any method in the stack returns true, the user is allowed to change it.
    
    Parameters:
    
    context - DSpace context
    
    request - HTTP request, in case it's needed. May be null.
    
    username - Username, if available. May be null.
    
    Returns:
    
    true if this method allows user to change ePerson password.
    
    Throws:
    
    SQLException - if database error
  - isImplicit
```
boolean isImplicit()
```
    Predicate, is this an implicit authentication method. An implicit method gets credentials from the environment (such as an HTTP request or even Java system properties) rather than the explicit username and password. For example, a method that reads the X.509 certificates in an HTTPS request is implicit.
    
    Returns:
    
    true if this method uses implicit authentication.
  - getSpecialGroups
```
List<Group> getSpecialGroups(Context context,
                             javax.servlet.http.HttpServletRequest request)
                      throws SQLException
```
    Get list of extra groups that user implicitly belongs to. Note that this method will be invoked regardless of the authentication status of the user (logged-in or not) e.g. a group that depends on the client network-address.
    It might make sense to implement this method by itself in a separate authentication method that just adds special groups, if the code doesn't belong with any existing auth method. The stackable authentication system was designed expressly to separate functions into "stacked" methods to keep your site-specific code modular and tidy.
    
    Parameters:
    
    context - A valid DSpace context.
    
    request - The request that started this operation, or null if not applicable.
    
    Returns:
    
    array of EPerson-group IDs, possibly 0-length, but never null.
    
    Throws:
    
    SQLException - if database error
  - areSpecialGroupsApplicable
```
default boolean areSpecialGroupsApplicable(Context context,
                                           javax.servlet.http.HttpServletRequest request)
```
    Returns true if the special groups returned by getSpecialGroups(Context, HttpServletRequest) should be implicitly be added to the groups related to the current user. By default this is true if the authentication method is the actual authentication mechanism used by the user.
    
    Parameters:
    
    context - A valid DSpace context.
    
    request - The request that started this operation, or null if not applicable.
    
    Returns:
    
    true is the special groups must be considered, false otherwise
  - authenticate
```
int authenticate(Context context,
                 String username,
                 String password,
                 String realm,
                 javax.servlet.http.HttpServletRequest request)
          throws SQLException
```
    Authenticate the given or implicit credentials. This is the heart of the authentication method: test the credentials for authenticity, and if accepted, attempt to match (or optionally, create) an EPerson. If an EPerson is found it is set in the Context that was passed.
    
    Parameters:
    
    context - DSpace context, will be modified (ePerson set) upon success.
    
    username - Username (or email address) when method is explicit. Use null for implicit method.
    
    password - Password for explicit auth, or null for implicit method.
    
    realm - Realm is an extra parameter used by some authentication methods, leave null if not applicable.
    
    request - The HTTP request that started this operation, or null if not applicable.
    
    Returns:
    
    One of: SUCCESS, BAD_CREDENTIALS, CERT_REQUIRED, NO_SUCH_USER, BAD_ARGS
    Meaning:
    SUCCESS - authenticated OK.
    BAD_CREDENTIALS - user exists, but credentials (e.g. passwd) don't match
    CERT_REQUIRED - not allowed to login this way without X.509 cert.
    NO_SUCH_USER - user not found using this method.
    BAD_ARGS - user/pw not appropriate for this method
    
    Throws:
    
    SQLException - if database error
  - loginPageURL
```
String loginPageURL(Context context,
                    javax.servlet.http.HttpServletRequest request,
                    javax.servlet.http.HttpServletResponse response)
```
    Get an external login page to which to redirect. Returns URL (as string) to which to redirect to obtain credentials (either password prompt or e.g. HTTPS port for client cert.); null means no redirect. Note: Starting with DSpace 7, session logins will be managed through the REST API. Therefore, only authn providers with external login pages (such as Shibboleth) should return a login page.
    
    Parameters:
    
    context - DSpace context, will be modified (ePerson set) upon success.
    
    request - The HTTP request that started this operation, or null if not applicable.
    
    response - The HTTP response from the servlet method.
    
    Returns:
    
    fully-qualified URL or null
  - getName
```
String getName()
```
    Returns a short name that uniquely identifies this authentication method
    
    Returns:
    
    The authentication method name
  - isUsed
```
boolean isUsed(Context context,
               javax.servlet.http.HttpServletRequest request)
```
    Get whether the authentication method is being used.
    
    Parameters:
    
    context - The DSpace context
    
    request - The current request
    
    Returns:
    
    whether the authentication method is being used.
  - canChangePassword
```
boolean canChangePassword(Context context,
                          EPerson ePerson,
                          String currentPassword)
```
    Check if the given current password is valid to change the password of the given ePerson
    
    Parameters:
    
    context - The DSpace context
    
    ePerson - the ePerson related to the password change
    
    currentPassword - The current password to check
    
    Returns:
    
    true if the provided password matches with current password

Interface AuthenticationMethod

Field Summary

Method Summary

Field Detail

SUCCESS

BAD_CREDENTIALS

CERT_REQUIRED

NO_SUCH_USER

BAD_ARGS

Method Detail

canSelfRegister

initEPerson

allowSetPassword

isImplicit

getSpecialGroups

areSpecialGroupsApplicable

authenticate

loginPageURL

getName

isUsed

canChangePassword