From: Darren Tucker <dtucker@dtucker.net>
Date: Fri, 2 Sep 2022 04:17:28 +0000 (+1000)
Subject: Remove arc4random_uniform from arc4random.c
X-Git-Tag: V_9_1_P1~30
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c83e467ead67a8cb48ef4bec8085d6fb880a2ff4;p=thirdparty%2Fopenssh-portable.git

Remove arc4random_uniform from arc4random.c

This was previously moved into its own file (matching OpenBSD) which
prematurely committed in commit 73541f2.
---

diff --git a/openbsd-compat/arc4random.c b/openbsd-compat/arc4random.c
index 2f91c2b2b..2751fb839 100644
--- a/openbsd-compat/arc4random.c
+++ b/openbsd-compat/arc4random.c
@@ -242,44 +242,6 @@ arc4random_buf(void *_buf, size_t n)
 }
 #endif /* !defined(HAVE_ARC4RANDOM_BUF) && defined(HAVE_ARC4RANDOM) */
 
-#ifndef HAVE_ARC4RANDOM_UNIFORM
-/*
- * Calculate a uniformly distributed random number less than upper_bound
- * avoiding "modulo bias".
- *
- * Uniformity is achieved by generating new random numbers until the one
- * returned is outside the range [0, 2**32 % upper_bound).  This
- * guarantees the selected random number will be inside
- * [2**32 % upper_bound, 2**32) which maps back to [0, upper_bound)
- * after reduction modulo upper_bound.
- */
-u_int32_t
-arc4random_uniform(u_int32_t upper_bound)
-{
-	u_int32_t r, min;
-
-	if (upper_bound < 2)
-		return 0;
-
-	/* 2**32 % x == (2**32 - x) % x */
-	min = -upper_bound % upper_bound;
-
-	/*
-	 * This could theoretically loop forever but each retry has
-	 * p > 0.5 (worst case, usually far better) of selecting a
-	 * number inside the range we need, so it should rarely need
-	 * to re-roll.
-	 */
-	for (;;) {
-		r = arc4random();
-		if (r >= min)
-			break;
-	}
-
-	return r % upper_bound;
-}
-#endif /* !HAVE_ARC4RANDOM_UNIFORM */
-
 #if 0
 /*-------- Test code for i386 --------*/
 #include <stdio.h>