marcsaeg 00/12/22 09:35:06
Modified: src/share/org/apache/tomcat/util Tag: tomcat_32
SessionIdGenerator.java
Log:
The PRNG is now initialized with a seed value to prevent the multi-second
delay seen on many platforms.
This code is based on Craig's changes to Catalina that address the same
issue there.
Revision Changes Path
No revision
No revision
1.3.2.3 +51 -7
jakarta-tomcat/src/share/org/apache/tomcat/util/SessionIdGenerator.java
Index: SessionIdGenerator.java
===================================================================
RCS file:
/home/cvs/jakarta-tomcat/src/share/org/apache/tomcat/util/SessionIdGenerator.java,v
retrieving revision 1.3.2.2
retrieving revision 1.3.2.3
diff -u -r1.3.2.2 -r1.3.2.3
--- SessionIdGenerator.java 2000/11/18 01:33:59 1.3.2.2
+++ SessionIdGenerator.java 2000/12/22 17:35:05 1.3.2.3
@@ -1,7 +1,7 @@
/*
- * $Header:
/home/cvs/jakarta-tomcat/src/share/org/apache/tomcat/util/SessionIdGenerator.java,v
1.3.2.2 2000/11/18 01:33:59 craigmcc Exp $
- * $Revision: 1.3.2.2 $
- * $Date: 2000/11/18 01:33:59 $
+ * $Header:
/home/cvs/jakarta-tomcat/src/share/org/apache/tomcat/util/SessionIdGenerator.java,v
1.3.2.3 2000/12/22 17:35:05 marcsaeg Exp $
+ * $Revision: 1.3.2.3 $
+ * $Date: 2000/12/22 17:35:05 $
*
* ====================================================================
*
@@ -114,7 +114,41 @@
*/
public final static long ticDifference = 2000;
- // ** NOTE that this must work together with get_jserv_session_balance()
+ /**
+ * A String initialization parameter used to increase the entropy of
+ * the initialization of our random number generator.
+ */
+ private static String entropy = null;
+
+
+ /**
+ * Return the entropy increaser value, or compute a semi-useful value
+ * if this String has not yet been set.
+ */
+ public static String getEntropy() {
+
+ // Calculate a semi-useful value if this has not been set
+ if (entropy == null)
+ setEntropy((new Object()).toString());
+
+ return (entropy);
+
+ }
+
+
+ /**
+ * Set the entropy increaser value.
+ *
+ * @param entropy The new entropy increaser value
+ */
+ public static void setEntropy(String newEntropy) {
+
+ entropy = newEntropy;
+
+ }
+
+
+ // ** NOTE that this must work together with get_jserv_session_balance()
// ** in jserv_balance.c
static synchronized public String getIdentifier (String jsIdent)
{
@@ -133,10 +167,20 @@
}
if (randomSource == null)
randomSource = new java.security.SecureRandom();
- }
+
+ // Set the seed PRNG's seed value
+ long seed = System.currentTimeMillis();
+ char entropy[] = getEntropy().toCharArray();
+ for (int i = 0; i < entropy.length; i++) {
+ long update = ((byte) entropy[i]) << ((i % 8)
* 8);
+ seed ^= update;
+ }
+ randomSource.setSeed(seed);
+ }
+
- // random value ..
- long n = randomSource.nextLong();
+ // random value ..
+ long n = randomSource.nextLong();
if (n < 0) n = -n;
n %= maxRandomLen;
// add maxLen to pad the leading characters with '0'; remove
