xref: /freebsd/contrib/netbsd-tests/lib/libc/stdlib/t_random.c (revision 43a5ec4eb41567cc92586503212743d89686d78f)
1 /* $NetBSD: t_random.c,v 1.3 2012/03/29 08:56:06 jruoho Exp $ */
2 
3 /*-
4  * Copyright (c) 2012 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Jukka Ruohonen.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 #include <sys/cdefs.h>
32 __RCSID("$NetBSD: t_random.c,v 1.3 2012/03/29 08:56:06 jruoho Exp $");
33 
34 #include <atf-c.h>
35 #include <stdio.h>
36 #include <stdlib.h>
37 
38 /*
39  * TODO: Add some general RNG tests (cf. the famous "diehard" tests?).
40  */
41 
42 ATF_TC(random_same);
43 ATF_TC_HEAD(random_same, tc)
44 {
45 	atf_tc_set_md_var(tc, "descr",
46 	    "Test that random(3) does not always return the same "
47 	    "value when the seed is initialized to zero");
48 }
49 
50 #define MAX_ITER 10
51 
52 ATF_TC_BODY(random_same, tc)
53 {
54 	long buf[MAX_ITER];
55 	size_t i, j;
56 
57 	/*
58 	 * See CVE-2012-1577.
59 	 */
60 	srandom(0);
61 
62 	for (i = 0; i < __arraycount(buf); i++) {
63 
64 		buf[i] = random();
65 
66 		for (j = 0; j < i; j++) {
67 
68 			(void)fprintf(stderr, "i = %zu, j = %zu: "
69 			    "%ld vs. %ld\n", i, j, buf[i], buf[j]);
70 
71 			ATF_CHECK(buf[i] != buf[j]);
72 		}
73 	}
74 }
75 
76 ATF_TP_ADD_TCS(tp)
77 {
78 
79 	ATF_TP_ADD_TC(tp, random_same);
80 
81 	return atf_no_error();
82 }
83