tests/lib/libc/stdlib/t_random.c

   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 }