Source for gnu.java.security.Properties

   1: /* Properties.java -- run-time configuration properties.
   2:    Copyright (C) 2003, 2004, 2006 Free Software Foundation, Inc.
   3: 
   4: This file is a 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 of the License, or (at
   9: your option) 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; if not, write to the Free Software
  18: Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301
  19: 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 gnu.java.security;
  40: 
  41: import gnu.java.security.Configuration;
  42: 
  43: import java.io.FileInputStream;
  44: import java.io.IOException;
  45: import java.security.AccessController;
  46: import java.security.PrivilegedAction;
  47: import java.util.HashMap;
  48: import java.util.PropertyPermission;
  49: import java.util.logging.Logger;
  50: 
  51: /**
  52:  * A global object containing build-specific properties that affect the
  53:  * behaviour of the generated binaries from this library.
  54:  */
  55: public final class Properties
  56: {
  57:   private static final Logger log = Logger.getLogger(Properties.class.getName());
  58: 
  59:   public static final String VERSION = "gnu.crypto.version";
  60: 
  61:   public static final String PROPERTIES_FILE = "gnu.crypto.properties.file";
  62: 
  63:   public static final String REPRODUCIBLE_PRNG = "gnu.crypto.with.reproducible.prng";
  64: 
  65:   public static final String CHECK_WEAK_KEYS = "gnu.crypto.with.check.for.weak.keys";
  66: 
  67:   public static final String DO_RSA_BLINDING = "gnu.crypto.with.rsa.blinding";
  68: 
  69:   private static final String TRUE = Boolean.TRUE.toString();
  70: 
  71:   private static final String FALSE = Boolean.FALSE.toString();
  72: 
  73:   private static final HashMap props = new HashMap();
  74: 
  75:   private static Properties singleton = null;
  76: 
  77:   private boolean reproducible = false;
  78: 
  79:   private boolean checkForWeakKeys = true;
  80: 
  81:   private boolean doRSABlinding = true;
  82: 
  83:   /** Trivial constructor to enforce Singleton pattern. */
  84:   private Properties()
  85:   {
  86:     super();
  87:     init();
  88:   }
  89: 
  90:   /**
  91:    * Returns the string representation of the library global configuration
  92:    * property with the designated <code>key</code>.
  93:    *
  94:    * @param key the case-insensitive, non-null and non-empty name of a
  95:    *          configuration property.
  96:    * @return the string representation of the designated property, or
  97:    *         <code>null</code> if such property is not yet set, or
  98:    *         <code>key</code> is empty.
  99:    */
 100:   public static final synchronized String getProperty(String key)
 101:   {
 102:     if (key == null)
 103:       return null;
 104:     SecurityManager sm = System.getSecurityManager();
 105:     if (sm != null)
 106:       sm.checkPermission(new PropertyPermission(key, "read"));
 107:     key = key.trim().toLowerCase();
 108:     if ("".equals(key))
 109:       return null;
 110:     return (String) props.get(key);
 111:   }
 112: 
 113:   /**
 114:    * Sets the value of a designated library global configuration property, to a
 115:    * string representation of what should be a legal value.
 116:    *
 117:    * @param key the case-insensitive, non-null and non-empty name of a
 118:    *          configuration property.
 119:    * @param value the non-null, non-empty string representation of a legal value
 120:    *          of the configuration property named by <code>key</code>.
 121:    */
 122:   public static final synchronized void setProperty(String key, String value)
 123:   {
 124:     if (key == null || value == null)
 125:       return;
 126:     key = key.trim().toLowerCase();
 127:     if ("".equals(key))
 128:       return;
 129:     if (key.equals(VERSION))
 130:       return;
 131:     value = value.trim();
 132:     if ("".equals(value))
 133:       return;
 134:     SecurityManager sm = System.getSecurityManager();
 135:     if (sm != null)
 136:       sm.checkPermission(new PropertyPermission(key, "write"));
 137:     if (key.equals(REPRODUCIBLE_PRNG)
 138:         && (value.equalsIgnoreCase(TRUE) || value.equalsIgnoreCase(FALSE)))
 139:       setReproducible(Boolean.valueOf(value).booleanValue());
 140:     else if (key.equals(CHECK_WEAK_KEYS)
 141:              && (value.equalsIgnoreCase(TRUE) || value.equalsIgnoreCase(FALSE)))
 142:       setCheckForWeakKeys(Boolean.valueOf(value).booleanValue());
 143:     else if (key.equals(DO_RSA_BLINDING)
 144:              && (value.equalsIgnoreCase(TRUE) || value.equalsIgnoreCase(FALSE)))
 145:       setDoRSABlinding(Boolean.valueOf(value).booleanValue());
 146:     else
 147:       props.put(key, value);
 148:   }
 149: 
 150:   /**
 151:    * A convenience method that returns, as a boolean, the library global
 152:    * configuration property indicating if the default Pseudo Random Number
 153:    * Generator produces, or not, the same bit stream when instantiated.
 154:    *
 155:    * @return <code>true</code> if the default PRNG produces the same bit
 156:    *         stream with every VM instance. Returns <code>false</code> if the
 157:    *         default PRNG is seeded with the time of day of its first
 158:    *         invocation.
 159:    */
 160:   public static final synchronized boolean isReproducible()
 161:   {
 162:     SecurityManager sm = System.getSecurityManager();
 163:     if (sm != null)
 164:       sm.checkPermission(new PropertyPermission(REPRODUCIBLE_PRNG, "read"));
 165:     return instance().reproducible;
 166:   }
 167: 
 168:   /**
 169:    * A convenience method that returns, as a boolean, the library global
 170:    * configuration property indicating if the implementations of symmetric key
 171:    * block ciphers check, or not, for possible/potential weak and semi-weak keys
 172:    * that may be produced in the course of generating round encryption and/or
 173:    * decryption keys.
 174:    *
 175:    * @return <code>true</code> if the cipher implementations check for weak
 176:    *         and semi-weak keys. Returns <code>false</code> if the cipher
 177:    *         implementations do not check for weak or semi-weak keys.
 178:    */
 179:   public static final synchronized boolean checkForWeakKeys()
 180:   {
 181:     SecurityManager sm = System.getSecurityManager();
 182:     if (sm != null)
 183:       sm.checkPermission(new PropertyPermission(CHECK_WEAK_KEYS, "read"));
 184:     return instance().checkForWeakKeys;
 185:   }
 186: 
 187:   /**
 188:    * A convenience method that returns, as a boolean, the library global
 189:    * configuration property indicating if RSA decryption (RSADP primitive),
 190:    * does, or not, blinding against timing attacks.
 191:    *
 192:    * @return <code>true</code> if the RSA decryption primitive includes a
 193:    *         blinding operation. Returns <code>false</code> if the RSA
 194:    *         decryption primitive does not include the additional blinding
 195:    *         operation.
 196:    */
 197:   public static final synchronized boolean doRSABlinding()
 198:   {
 199:     SecurityManager sm = System.getSecurityManager();
 200:     if (sm != null)
 201:       sm.checkPermission(new PropertyPermission(DO_RSA_BLINDING, "read"));
 202:     return instance().doRSABlinding;
 203:   }
 204: 
 205:   /**
 206:    * A convenience method to set the global property for reproducibility of the
 207:    * default PRNG bit stream output.
 208:    *
 209:    * @param value if <code>true</code> then the default PRNG bit stream output
 210:    *          is the same with every invocation of the VM.
 211:    */
 212:   public static final synchronized void setReproducible(final boolean value)
 213:   {
 214:     SecurityManager sm = System.getSecurityManager();
 215:     if (sm != null)
 216:       sm.checkPermission(new PropertyPermission(REPRODUCIBLE_PRNG, "write"));
 217:     instance().reproducible = value;
 218:     props.put(REPRODUCIBLE_PRNG, String.valueOf(value));
 219:   }
 220: 
 221:   /**
 222:    * A convenience method to set the global property for checking for weak and
 223:    * semi-weak cipher keys.
 224:    *
 225:    * @param value if <code>true</code> then the cipher implementations will
 226:    *          invoke additional checks for weak and semi-weak key values that
 227:    *          may get generated.
 228:    */
 229:   public static final synchronized void setCheckForWeakKeys(final boolean value)
 230:   {
 231:     SecurityManager sm = System.getSecurityManager();
 232:     if (sm != null)
 233:       sm.checkPermission(new PropertyPermission(CHECK_WEAK_KEYS, "write"));
 234:     instance().checkForWeakKeys = value;
 235:     props.put(CHECK_WEAK_KEYS, String.valueOf(value));
 236:   }
 237: 
 238:   /**
 239:    * A convenience method to set the global property fo adding a blinding
 240:    * operation when executing the RSA decryption primitive.
 241:    *
 242:    * @param value if <code>true</code> then the code for performing the RSA
 243:    *          decryption primitive will include a blinding operation.
 244:    */
 245:   public static final synchronized void setDoRSABlinding(final boolean value)
 246:   {
 247:     SecurityManager sm = System.getSecurityManager();
 248:     if (sm != null)
 249:       sm.checkPermission(new PropertyPermission(DO_RSA_BLINDING, "write"));
 250:     instance().doRSABlinding = value;
 251:     props.put(DO_RSA_BLINDING, String.valueOf(value));
 252:   }
 253: 
 254:   private static final synchronized Properties instance()
 255:   {
 256:     if (singleton == null)
 257:       singleton = new Properties();
 258:     return singleton;
 259:   }
 260: 
 261:   private void init()
 262:   {
 263:     // default values
 264:     props.put(REPRODUCIBLE_PRNG, (reproducible ? "true" : "false"));
 265:     props.put(CHECK_WEAK_KEYS, (checkForWeakKeys ? "true" : "false"));
 266:     props.put(DO_RSA_BLINDING, (doRSABlinding ? "true" : "false"));
 267:     // 1. allow site-wide override by reading a properties file
 268:     String propFile = null;
 269:     try
 270:       {
 271:         propFile = (String) AccessController.doPrivileged(new PrivilegedAction()
 272:         {
 273:           public Object run()
 274:           {
 275:             return System.getProperty(PROPERTIES_FILE);
 276:           }
 277:         });
 278:       }
 279:     catch (SecurityException se)
 280:       {
 281:         if (Configuration.DEBUG)
 282:           log.fine("Reading property " + PROPERTIES_FILE + " not allowed. Ignored.");
 283:       }
 284:     if (propFile != null)
 285:       {
 286:         try
 287:           {
 288:             final java.util.Properties temp = new java.util.Properties();
 289:             final FileInputStream fin = new FileInputStream(propFile);
 290:             temp.load(fin);
 291:             temp.list(System.out);
 292:             props.putAll(temp);
 293:           }
 294:         catch (IOException ioe)
 295:           {
 296:             if (Configuration.DEBUG)
 297:               log.fine("IO error reading " + propFile + ": " + ioe.getMessage());
 298:           }
 299:         catch (SecurityException se)
 300:           {
 301:             if (Configuration.DEBUG)
 302:               log.fine("Security error reading " + propFile + ": "
 303:                        + se.getMessage());
 304:           }
 305:       }
 306:     // 2. allow vm-specific override by allowing -D options in launcher
 307:     handleBooleanProperty(REPRODUCIBLE_PRNG);
 308:     handleBooleanProperty(CHECK_WEAK_KEYS);
 309:     handleBooleanProperty(DO_RSA_BLINDING);
 310:     // re-sync the 'known' properties
 311:     reproducible = Boolean.valueOf((String) props.get(REPRODUCIBLE_PRNG)).booleanValue();
 312:     checkForWeakKeys = Boolean.valueOf((String) props.get(CHECK_WEAK_KEYS)).booleanValue();
 313:     doRSABlinding = Boolean.valueOf((String) props.get(DO_RSA_BLINDING)).booleanValue();
 314:     // This does not change.
 315:     props.put(VERSION, Registry.VERSION_STRING);
 316:   }
 317: 
 318:   private void handleBooleanProperty(final String name)
 319:   {
 320:     String s = null;
 321:     try
 322:       {
 323:         s = System.getProperty(name);
 324:       }
 325:     catch (SecurityException x)
 326:       {
 327:         if (Configuration.DEBUG)
 328:           log.fine("SecurityManager forbids reading system properties. Ignored");
 329:       }
 330:     if (s != null)
 331:       {
 332:         s = s.trim().toLowerCase();
 333:         // we have to test for explicit "true" or "false". anything else may
 334:         // hide valid value set previously
 335:         if (s.equals(TRUE) || s.equals(FALSE))
 336:           {
 337:             if (Configuration.DEBUG)
 338:               log.fine("Setting " + name + " to '" + s + "'");
 339:             props.put(name, s);
 340:           }
 341:         else
 342:           {
 343:             if (Configuration.DEBUG)
 344:               log.fine("Invalid value for -D" + name + ": " + s + ". Ignored");
 345:           }
 346:       }
 347:   }
 348: }