egovframework.rfc3.iam.security.authentication.rememberme
Class TokenBasedRememberMeServices

java.lang.Object
  egovframework.rfc3.iam.security.authentication.rememberme.AbstractRememberMeServices
      egovframework.rfc3.iam.security.authentication.rememberme.TokenBasedRememberMeServices

All Implemented Interfaces:

RFC3RememberMeServices, org.springframework.beans.factory.InitializingBean, org.springframework.security.web.authentication.logout.LogoutHandler

public class TokenBasedRememberMeServices
extends AbstractRememberMeServices

Identifies previously remembered users by a Base-64 encoded cookie.

This implementation does not rely on an external database, so is attractive for simple applications. The cookie will be valid for a specific period from the date of the last AbstractRememberMeServices.loginSuccess(HttpServletRequest, HttpServletResponse, Authentication). As per the interface contract, this method will only be called when the principal completes a successful interactive authentication. As such the time period commences from the last authentication attempt where they furnished credentials - not the time period they last logged in via remember-me. The implementation will only send a remember-me token if the parameter defined by AbstractRememberMeServices.setParameter(String) is present.

An UserDetailsService is required by this implementation, so that it can construct a valid Authentication from the returned UserDetails. This is also necessary so that the user's password is available and can be checked as part of the encoded cookie.

The cookie encoded by this implementation adopts the following form:

 username + ":" + expiryTime + ":" + Md5Hex(username + ":" + expiryTime + ":" + password + ":" + key)
 

As such, if the user changes their password, any remember-me token will be invalidated. Equally, the system administrator may invalidate every remember-me token on issue by changing the key. This provides some reasonable approaches to recovering from a remember-me token being left on a public machine (e.g. kiosk system, Internet cafe etc). Most importantly, at no time is the user's password ever sent to the user agent, providing an important security safeguard. Unfortunately the username is necessary in this implementation (as we do not want to rely on a database for remember-me services). High security applications should be aware of this occasionally undesired disclosure of a valid username.

This is a basic remember-me implementation which is suitable for many applications. However, we recommend a database-based implementation if you require a more secure remember-me approach (see PersistentTokenBasedRememberMeServices).

By default the tokens will be valid for 14 days from the last successful authentication attempt. This can be changed using AbstractRememberMeServices.setTokenValiditySeconds(int). If this value is less than zero, the expiryTime will remain at 14 days, but the negative value will be used for the maxAge property of the cookie, meaning that it will not be stored when the browser is closed.

Author:

Ben Alex

Field Summary

Fields inherited from class egovframework.rfc3.iam.security.authentication.rememberme.AbstractRememberMeServices

DEFAULT_PARAMETER, SPRING_SECURITY_REMEMBER_ME_COOKIE_KEY, TWO_WEEKS_S

Constructor Summary

TokenBasedRememberMeServices()

Method Summary

void	onLoginSuccess(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response, org.springframework.security.core.Authentication successfulAuthentication) Called from loginSuccess when a remember-me login has been requested.

Methods inherited from class egovframework.rfc3.iam.security.authentication.rememberme.AbstractRememberMeServices

afterPropertiesSet, autoLogin, extractRememberMeCookie, getKey, getParameter, loginFail, loginSuccess, logout, onCookiesValidate, setAlwaysRemember, setAuthenticationDetailsSource, setCookieName, setKey, setParameter, setTokenValiditySeconds, setUserDetailsService, setUseSecureCookie

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

TokenBasedRememberMeServices

public TokenBasedRememberMeServices()

Method Detail

onLoginSuccess

public void onLoginSuccess(javax.servlet.http.HttpServletRequest request,
                           javax.servlet.http.HttpServletResponse response,
                           org.springframework.security.core.Authentication successfulAuthentication)

Description copied from class: AbstractRememberMeServices

Called from loginSuccess when a remember-me login has been requested. Typically implemented by subclasses to set a remember-me cookie and potentially store a record of it if the implementation requires this.