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-rw-r--r--libjava/classpath/gnu/java/security/jce/prng/SecureRandomAdapter.java121
1 files changed, 99 insertions, 22 deletions
diff --git a/libjava/classpath/gnu/java/security/jce/prng/SecureRandomAdapter.java b/libjava/classpath/gnu/java/security/jce/prng/SecureRandomAdapter.java
index 5be402ff005..5877e3edb6c 100644
--- a/libjava/classpath/gnu/java/security/jce/prng/SecureRandomAdapter.java
+++ b/libjava/classpath/gnu/java/security/jce/prng/SecureRandomAdapter.java
@@ -38,35 +38,57 @@ 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;
/**
- * The implementation of a generic {@link java.security.SecureRandom} adapter
- * class to wrap GNU PRNG instances based on Message Digest algorithms.
- * <p>
- * This class defines the <i>Service Provider Interface</i> (<b>SPI</b>) for
+ * <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>
- * All the abstract methods in the {@link SecureRandomSpi} class are implemented
- * by this class and all its sub-classes.
+ * 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>
*/
-abstract class SecureRandomAdapter
- extends SecureRandomSpi
+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";
+
/**
- * Trivial protected constructor.
- *
+ * <p>Trivial protected constructor.</p>
+ *
* @param mdName the canonical name of the underlying hash algorithm.
*/
protected SecureRandomAdapter(String mdName)
@@ -74,23 +96,77 @@ abstract class SecureRandomAdapter
super();
this.mdName = mdName;
- adaptee.init(Collections.singletonMap(MDGenerator.MD_NAME, 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)
{
- if (numBytes < 1)
- return new byte[0];
-
- byte[] result = new byte[numBytes];
- this.engineNextBytes(result);
- return result;
+ return getSeed(numBytes);
}
public void engineNextBytes(byte[] bytes)
{
- if (! adaptee.isInitialised())
- this.engineSetSeed(new byte[0]);
+ if (!isSeeded)
+ {
+ engineSetSeed(engineGenerateSeed(32));
+ }
try
{
adaptee.nextBytes(bytes, 0, bytes.length);
@@ -102,6 +178,7 @@ abstract class SecureRandomAdapter
public void engineSetSeed(byte[] seed)
{
- adaptee.addRandomBytes(seed);
+ adaptee.addRandomBytes (seed);
+ isSeeded = true;
}
}