libjava/javax/security/auth/login/LoginContext.java

   1 /* LoginContext.java
   2    Copyright (C) 2004 Free Software Foundation, Inc.
   3
   4 This file is part of GNU Classpath.
   5
   6 GNU Classpath is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Classpath is distributed in the hope that it will be useful, but
  12 WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Classpath; see the file COPYING.  If not, write to the
  18 Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  19 02111-1307 USA.
  20
  21 Linking this library statically or dynamically with other modules is
  22 making a combined work based on this library.  Thus, the terms and
  23 conditions of the GNU General Public License cover the whole
  24 combination.
  25
  26 As a special exception, the copyright holders of this library give you
  27 permission to link this library with independent modules to produce an
  28 executable, regardless of the license terms of these independent
  29 modules, and to copy and distribute the resulting executable under
  30 terms of your choice, provided that you also meet, for each linked
  31 independent module, the terms and conditions of the license of that
  32 module.  An independent module is a module which is not derived from
  33 or based on this library.  If you modify this library, you may extend
  34 this exception to your version of the library, but you are not
  35 obligated to do so.  If you do not wish to do so, delete this
  36 exception statement from your version. */
  37
  38
  39 package javax.security.auth.login;
  40
  41 import gnu.java.security.action.GetSecurityPropertyAction;
  42
  43 import java.security.AccessController;
  44
  45 import java.util.HashMap;
  46 import java.util.Map;
  47
  48 import javax.security.auth.Subject;
  49 import javax.security.auth.callback.CallbackHandler;
  50 import javax.security.auth.spi.LoginModule;
  51
  52 public class LoginContext
  53 {
  54
  55   private static final String OTHER = "other";
  56
  57   private final String name;
  58   private final CallbackHandler cbHandler;
  59   private final Subject subject;
  60   private final AppConfigurationEntry[] entries;
  61   private final LoginModule[] modules;
  62   private final Map sharedState;
  63
  64   public LoginContext (final String name) throws LoginException
  65   {
  66     this (name, new Subject(), defaultHandler());
  67   }
  68
  69   public LoginContext (final String name, final CallbackHandler cbHandler)
  70     throws LoginException
  71   {
  72     this (name, new Subject(), cbHandler);
  73   }
  74
  75   public LoginContext (final String name, final Subject subject)
  76     throws LoginException
  77   {
  78     this (name, subject, defaultHandler());
  79   }
  80
  81   public LoginContext (final String name, final Subject subject,
  82                        final CallbackHandler cbHandler)
  83     throws LoginException
  84   {
  85     Configuration config = Configuration.getConfig();
  86     AppConfigurationEntry[] entries = config.getAppConfigurationEntry (name);
  87     if (entries == null)
  88       entries = config.getAppConfigurationEntry (OTHER);
  89     if (entries == null)
  90       throw new LoginException ("no configured modules for application "
  91                                 + name);
  92     this.entries = entries;
  93     modules = new LoginModule[entries.length];
  94     sharedState = new HashMap();
  95     for (int i = 0; i < entries.length; i++)
  96       modules[i] = lookupModule (entries[i], subject, sharedState);
  97     this.name = name;
  98     this.subject = subject;
  99     this.cbHandler = cbHandler;
 100   }
 101
 102   /**
 103    * Returns the authenticated subject, or the parameter passed to one
 104    * of the constructors. <code>null</code> is returned if the previous
 105    * login attempt failed and there was no subject provided.
 106    *
 107    * @return The subject, or null.
 108    */
 109   public Subject getSubject()
 110   {
 111     return subject;
 112   }
 113
 114   /**
 115    * Logs a subject in, using all login modules configured for this
 116    * application. This method will call the {@link LoginModule#login()}
 117    * method of each module configured for this application, stopping
 118    * if a REQUISITE module fails or if a SUFFICIENT module succeeds. If
 119    * the overall login attempt fails, a {@link LoginException} will be
 120    * thrown.
 121    *
 122    * @throws LoginException If logging in fails.
 123    */
 124   public void login() throws LoginException
 125   {
 126     boolean failure = false;
 127     for (int i = 0; i < modules.length; i++)
 128       {
 129         try
 130           {
 131             boolean result = modules[i].login();
 132             if (!result)
 133               {
 134                 if (entries[i].getControlFlag() ==
 135                     AppConfigurationEntry.LoginModuleControlFlag.REQUISITE)
 136                   throw new LoginException ("REQUISITE module " + entries[i].getLoginModuleName()
 137                                             + " failed");
 138                 else if (entries[i].getControlFlag() ==
 139                          AppConfigurationEntry.LoginModuleControlFlag.REQUIRED)
 140                   failure = true;
 141               }
 142             else
 143               {
 144                 if (entries[i].getControlFlag() ==
 145                     AppConfigurationEntry.LoginModuleControlFlag.SUFFICIENT)
 146                   break;
 147               }
 148           }
 149         catch (LoginException le)
 150           {
 151             if (entries[i].getControlFlag() !=
 152                 AppConfigurationEntry.LoginModuleControlFlag.REQUISITE)
 153               continue;
 154             for (int j = 0; j < modules.length; j++)
 155               modules[i].abort();
 156             throw le;
 157           }
 158       }
 159     if (failure)
 160       throw new LoginException ("not all REQUIRED modules succeeded");
 161
 162     for (int i = 0; i < modules.length; i++)
 163       modules[i].commit();
 164   }
 165
 166   /**
 167    * Logs a subject out, cleaning up any state that may be in memory.
 168    *
 169    * @throws LoginException If logging out fails.
 170    */
 171   public void logout() throws LoginException
 172   {
 173     for (int i = 0; i < modules.length; i++)
 174       modules[i].logout();
 175   }
 176
 177   // Own methods.
 178
 179   /**
 180    * Fetch the default callback handler, based on the
 181    * auth.login.defaultCallbackHandler property, or null if it is not
 182    * set.
 183    */
 184   private static CallbackHandler defaultHandler()
 185   {
 186     GetSecurityPropertyAction act =
 187       new GetSecurityPropertyAction ("auth.login.defaultCallbackHandler");
 188     String classname = (String) AccessController.doPrivileged (act);
 189     if (classname != null)
 190       {
 191         try
 192           {
 193             return (CallbackHandler) Class.forName (classname).newInstance();
 194           }
 195         catch (ClassNotFoundException cnfe)
 196           {
 197             return null;
 198           }
 199         catch (ClassCastException cce)
 200           {
 201             return null;
 202           }
 203         catch (IllegalAccessException iae)
 204           {
 205             return null;
 206           }
 207         catch (InstantiationException ie)
 208           {
 209             return null;
 210           }
 211       }
 212     return null;
 213   }
 214
 215   private LoginModule lookupModule (AppConfigurationEntry entry,
 216                                     Subject subject, Map sharedState)
 217     throws LoginException
 218   {
 219     LoginModule module = null;
 220     Exception cause = null;
 221     try
 222       {
 223         module = (LoginModule) Class.forName (entry.getLoginModuleName()).newInstance();
 224       }
 225     catch (ClassNotFoundException cnfe)
 226       {
 227         cause = cnfe;
 228       }
 229     catch (ClassCastException cce)
 230       {
 231         cause = cce;
 232       }
 233     catch (IllegalAccessException iae)
 234       {
 235         cause = iae;
 236       }
 237     catch (InstantiationException ie)
 238       {
 239         cause = ie;
 240       }
 241
 242     if (cause != null)
 243       {
 244         LoginException le = new LoginException ("could not load module "
 245                                                 + entry.getLoginModuleName());
 246         le.initCause (cause);
 247         throw le;
 248       }
 249
 250     module.initialize (subject, cbHandler, sharedState, entry.getOptions());
 251     return module;
 252   }
 253 }