X-Git-Url: https://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/bf5d7992ce29e9fb006a5b6770bd3457b9b0f18b..1ec412d97ddac6bd184c645815037e29fd84fb90:/common/random.c

diff --git a/common/random.c b/common/random.c
index 62d0cbeb..5658683d 100644
--- a/common/random.c
+++ b/common/random.c
@@ -1,6 +1,6 @@
 #include "random.h"
 
-static uint64_t next_random = 1;
+static uint32_t g_nextrandom;
 
 /* Generates a (non-cryptographically secure) 32-bit random number.
  *
@@ -8,12 +8,23 @@ static uint64_t next_random = 1;
  * method of seeding with the time it took to call "autoseed" from first run.
  * 
  * https://github.com/Proxmark/proxmark3/pull/209/commits/f9c1dcd9f6e68a8c07cffed697a9c4c8caed6015
+ *
+ * Iceman,  rand needs to be fast.
+ * https://software.intel.com/en-us/articles/fast-random-number-generator-on-the-intel-pentiumr-4-processor/
  */
+ 
+inline void fast_prand(){
+	fast_prandEx(GetTickCount());
+}
+inline void fast_prandEx(uint32_t seed) {
+	g_nextrandom = seed;
+}
+ 
 uint32_t prand() {
-	if (next_random == 1)
-		next_random = GetTickCount();
-
-	next_random = next_random * 6364136223846793005 + 1;
-	return (uint32_t)(next_random >> 32) % 0xffffffff;
+//	g_nextrandom *= 6364136223846793005;
+//	g_nextrandom += 1;
+//return (uint32_t)(g_nextrandom >> 32) % 0xffffffff;
+	g_nextrandom = (214013 * g_nextrandom + 2531011);
+	return (g_nextrandom>>16) & 0xFFFF;
 }