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Diffstat (limited to 'gcc-4.4.3/libjava/classpath/gnu/java/security/jce/prng/SecureRandomAdapter.java')
| -rw-r--r-- | gcc-4.4.3/libjava/classpath/gnu/java/security/jce/prng/SecureRandomAdapter.java | 184 |
1 files changed, 184 insertions, 0 deletions
diff --git a/gcc-4.4.3/libjava/classpath/gnu/java/security/jce/prng/SecureRandomAdapter.java b/gcc-4.4.3/libjava/classpath/gnu/java/security/jce/prng/SecureRandomAdapter.java new file mode 100644 index 000000000..5877e3edb --- /dev/null +++ b/gcc-4.4.3/libjava/classpath/gnu/java/security/jce/prng/SecureRandomAdapter.java @@ -0,0 +1,184 @@ +/* SecureRandomAdapter.java -- + Copyright (C) 2001, 2002, 2003, 2006 Free Software Foundation, Inc. + +This file is a part of GNU Classpath. + +GNU Classpath is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 2 of the License, or (at +your option) any later version. + +GNU Classpath is distributed in the hope that it will be useful, but +WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +General Public License for more details. + +You should have received a copy of the GNU General Public License +along with GNU Classpath; if not, write to the Free Software +Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 +USA + +Linking this library statically or dynamically with other modules is +making a combined work based on this library. Thus, the terms and +conditions of the GNU General Public License cover the whole +combination. + +As a special exception, the copyright holders of this library give you +permission to link this library with independent modules to produce an +executable, regardless of the license terms of these independent +modules, and to copy and distribute the resulting executable under +terms of your choice, provided that you also meet, for each linked +independent module, the terms and conditions of the license of that +module. An independent module is a module which is not derived from +or based on this library. If you modify this library, you may extend +this exception to your version of the library, but you are not +obligated to do so. If you do not wish to do so, delete this +exception statement from your version. */ + + +package gnu.java.security.jce.prng; + +import gnu.java.security.action.GetSecurityPropertyAction; +import gnu.classpath.SystemProperties; +import gnu.java.security.prng.LimitReachedException; +import gnu.java.security.prng.MDGenerator; + +import java.security.AccessController; +import java.security.SecureRandom; +import java.security.SecureRandomSpi; + +import java.util.Collections; +import java.util.logging.Level; +import java.util.logging.Logger; + +import java.io.InputStream; +import java.io.IOException; + +import java.net.MalformedURLException; +import java.net.URL; + +/** + * <p>The implementation of a generic {@link java.security.SecureRandom} adapter + * class to wrap gnu.crypto prng instances based on Message Digest algorithms.</p> + * + * <p>This class defines the <i>Service Provider Interface</i> (<b>SPI</b>) for + * the {@link java.security.SecureRandom} class, which provides the + * functionality of a cryptographically strong pseudo-random number generator.</p> + * + * <p>All the abstract methods in the {@link SecureRandomSpi} class are + * implemented by this class and all its sub-classes.</p> + */ +public abstract class SecureRandomAdapter + extends SecureRandomSpi +{ + + private boolean isSeeded = false; + + /** Our underlying prng instance. */ + private MDGenerator adaptee = new MDGenerator(); + + /** The name of the message digest algorithm used by the adaptee. */ + private String mdName; + + private static final Logger logger = + Logger.getLogger(SecureRandom.class.getName()); + + private static final String SECURERANDOM_SOURCE = "securerandom.source"; + private static final String JAVA_SECURITY_EGD = "java.security.egd"; + + /** + * <p>Trivial protected constructor.</p> + * + * @param mdName the canonical name of the underlying hash algorithm. + */ + protected SecureRandomAdapter(String mdName) + { + super(); + + this.mdName = mdName; + adaptee.init (Collections.singletonMap (MDGenerator.MD_NAME, mdName)); + } + + public static final byte[] getSeed(int numBytes) + { + URL sourceUrl = null; + String urlStr = null; + + byte[] buffer = new byte[numBytes]; + + GetSecurityPropertyAction action = + new GetSecurityPropertyAction(SECURERANDOM_SOURCE); + try + { + urlStr = (String) AccessController.doPrivileged(action); + if (urlStr != null) + sourceUrl = new URL(urlStr); + } + catch (MalformedURLException ignored) + { + logger.log(Level.WARNING, + SECURERANDOM_SOURCE + " property is malformed: {0}", + urlStr); + } + + if (sourceUrl == null) + { + try + { + urlStr = SystemProperties.getProperty(JAVA_SECURITY_EGD); + if (urlStr != null) + sourceUrl = new URL(urlStr); + } + catch (MalformedURLException mue) + { + logger.log(Level.WARNING, + JAVA_SECURITY_EGD + " property is malformed: {0}", + urlStr); + } + } + + if (sourceUrl != null) + { + try + { + InputStream in = sourceUrl.openStream(); + in.read(buffer); + return buffer; + } + catch (IOException ioe) + { + logger.log(Level.FINE, "error reading random bytes", ioe); + } + } + + // If we get here, we did not get any seed from a property URL. + VMSecureRandom.generateSeed(buffer, 0, buffer.length); + return buffer; + } + + public byte[] engineGenerateSeed(int numBytes) + { + return getSeed(numBytes); + } + + public void engineNextBytes(byte[] bytes) + { + if (!isSeeded) + { + engineSetSeed(engineGenerateSeed(32)); + } + try + { + adaptee.nextBytes(bytes, 0, bytes.length); + } + catch (LimitReachedException ignored) + { + } + } + + public void engineSetSeed(byte[] seed) + { + adaptee.addRandomBytes (seed); + isSeeded = true; + } +} |