From 58ea61ba2a747e4f0beb3afcbbdea8ada5119143 Mon Sep 17 00:00:00 2001 From: Damien Miller Date: Wed, 4 Jun 2008 10:54:00 +1000 Subject: - (djm) [openbsd-compat/bsd-arc4random.c] Fix math bug that caused bias in arc4random_uniform with upper_bound in (2^30,2*31). Note that OpenSSH did not make requests with upper bounds in this range. --- openbsd-compat/bsd-arc4random.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'openbsd-compat/bsd-arc4random.c') diff --git a/openbsd-compat/bsd-arc4random.c b/openbsd-compat/bsd-arc4random.c index 92e7e7b58..9d4c8690e 100644 --- a/openbsd-compat/bsd-arc4random.c +++ b/openbsd-compat/bsd-arc4random.c @@ -129,7 +129,7 @@ arc4random_uniform(u_int32_t upper_bound) min = 1 + ~upper_bound; /* 2**32 - upper_bound */ else { /* (2**32 - (x * 2)) % x == 2**32 % x when x <= 2**31 */ - min = ((0xffffffff - (upper_bound << 2)) + 1) % upper_bound; + min = ((0xffffffff - (upper_bound * 2)) + 1) % upper_bound; } #endif -- cgit v1.2.3