From 1b5a72829324a0d2fa327a270caea8fd02ae8779 Mon Sep 17 00:00:00 2001
From: Mark Andrews <marka@isc.org>
Date: Tue, 5 Aug 2003 00:08:30 +0000
Subject: [PATCH] 1499.   [bug]           isc_random need to be seeded better
 if arc4random()                         is not used.

---
 CHANGES          |  3 +++
 lib/isc/random.c | 12 ++++++++++--
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/CHANGES b/CHANGES
index de32cc2503..55687d4223 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,3 +1,6 @@
+1499.	[bug]		isc_random need to be seeded better if arc4random()
+			is not used.
+
 1498.	[port]		bsdos: 5.x support.
 
 1497.	[placeholder]
diff --git a/lib/isc/random.c b/lib/isc/random.c
index 9091cbf1c3..aa495e8348 100644
--- a/lib/isc/random.c
+++ b/lib/isc/random.c
@@ -15,7 +15,7 @@
  * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: random.c,v 1.17 2002/12/05 04:36:26 marka Exp $ */
+/* $Id: random.c,v 1.18 2003/08/05 00:08:30 marka Exp $ */
 
 #include <config.h>
 
@@ -34,7 +34,15 @@ static void
 initialize_rand(void)
 {
 #ifndef HAVE_ARC4RANDOM
-	srand(time(NULL));
+	unsigned int pid = getpid();
+	
+	/*
+	 * The low bits of pid generally change faster.
+	 * Xor them with the high bits of time which change slowly.
+	 */
+	pid = ((pid << 16) & 0xffff0000) | ((pid >> 16) & 0xffff);
+
+	srand(time(NULL) ^ pid);
 #endif
 }