Patch: FYI: security bug fixes

[Tom Tromey <tromey at redhat dot com>]

I'm checking this in.
This fixes a couple of security bugs.

Tom

Index: ChangeLog
from  Tom Tromey  <tromey@redhat.com>
	* gnu/java/security/provider/SHA1PRNG.java (engineNextBytes):
	Rewrote.
	* java/security/SecureRandom.java (setSeed(long)): Don't set seed
	if secureRandomSpi is not initialized.

Index: gnu/java/security/provider/SHA1PRNG.java
===================================================================
RCS file: /cvs/gcc/gcc/libjava/gnu/java/security/provider/SHA1PRNG.java,v
retrieving revision 1.2
diff -u -r1.2 SHA1PRNG.java
--- gnu/java/security/provider/SHA1PRNG.java 2001/09/23 01:05:55 1.2
+++ gnu/java/security/provider/SHA1PRNG.java 2001/10/18 00:04:23
@@ -1,5 +1,5 @@
 /* SHA1PRNG.java --- Secure Random SPI SHA1PRNG
-   Copyright (C) 1999 Free Software Foundation, Inc.
+   Copyright (C) 1999, 2001 Free Software Foundation, Inc.
 
 This file is part of GNU Classpath.
 
@@ -73,29 +73,26 @@
 
   public void engineNextBytes(byte[] bytes)
   {
-
-    if( bytes.length < (20 - datapos) ) {
-      System.arraycopy( data, datapos, bytes, 0, bytes.length);
-      datapos += bytes.length;
-      return;
-    }
-
-    int i, blen = bytes.length, bpos = 0;
-    byte digestdata[];
-    while( bpos < blen ) {
-      i = 20 - datapos;
-      System.arraycopy( data, datapos, bytes, bpos, i);
-      bpos += i;
-      datapos += i;
-      if( datapos >= 20) {
-	//System.out.println( (0 + 20) + "\n" + (20 + 20) );
-	System.arraycopy( seed, 0, data, 20, 20);
-	digestdata = digest.digest( data );
-	System.arraycopy( digestdata, 0, data, 0, 20);
-	datapos = 0;
+    int loc = 0;
+    while (loc < bytes.length)
+      {
+	int copy = Math.min (bytes.length - loc, 20 - datapos);
+
+	if (copy > 0)
+	  {
+	    System.arraycopy (data, datapos, bytes, loc, copy);
+	    datapos += copy;
+	    loc += copy;
+	  }
+	else
+	  {
+	    // No data ready for copying, so refill our buffer.
+	    System.arraycopy( seed, 0, data, 20, 20);
+	    byte[] digestdata = digest.digest( data );
+	    System.arraycopy( digestdata, 0, data, 0, 20);
+	    datapos = 0;
+	  }
       }
-    }
-
   }
 
   public byte[] engineGenerateSeed(int numBytes)
Index: java/security/SecureRandom.java
===================================================================
RCS file: /cvs/gcc/gcc/libjava/java/security/SecureRandom.java,v
retrieving revision 1.2
diff -u -r1.2 SecureRandom.java
--- java/security/SecureRandom.java 2001/04/25 15:45:12 1.2
+++ java/security/SecureRandom.java 2001/10/18 00:04:24
@@ -1,5 +1,5 @@
 /* SecureRandom.java --- Secure Random class implmentation
-   Copyright (C) 1999 Free Software Foundation, Inc.
+   Copyright (C) 1999, 2001 Free Software Foundation, Inc.
 
 This file is part of GNU Classpath.
 
@@ -52,7 +52,7 @@
      new SecureRandom by instantating the first SecureRandom 
      algorithm in the default security provier. 
 
-     It is not seeded and should be seeded using setseed or else
+     It is not seeded and should be seeded using setSeed or else
      on the first call to getnextBytes it will force a seed.
 
      It is maintained for backwards compatability and programs
@@ -267,12 +267,24 @@
    */
   public void setSeed(long seed)
   {
-    byte tmp[] = { (byte) (0xff & (seed >> 56)), (byte) (0xff & (seed >> 48)),
-      (byte) (0xff & (seed >> 40)), (byte) (0xff & (seed >> 32)),
-      (byte) (0xff & (seed >> 24)), (byte) (0xff & (seed >> 16)),
-      (byte) (0xff & (seed >> 8)), (byte) (0xff & seed)
-    };
-    secureRandomSpi.engineSetSeed(tmp);
+    // This particular setSeed will be called by Random.Random(), via
+    // our own constructor, before secureRandomSpi is initialized.  In
+    // this case we can't call a method on secureRandomSpi, and we
+    // definitely don't want to throw a NullPointerException.
+    // Therefore we test.
+    if (secureRandomSpi != null)
+      {
+        byte tmp[] = { (byte) (0xff & (seed >> 56)),
+		       (byte) (0xff & (seed >> 48)),
+		       (byte) (0xff & (seed >> 40)),
+		       (byte) (0xff & (seed >> 32)),
+		       (byte) (0xff & (seed >> 24)),
+		       (byte) (0xff & (seed >> 16)),
+		       (byte) (0xff & (seed >> 8)),
+		       (byte) (0xff & seed)
+	};
+	secureRandomSpi.engineSetSeed(tmp);
+      }
   }
 
   /**