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Diffstat (limited to 'src/regress/lib/libc/explicit_bzero/explicit_bzero.c')
-rw-r--r--src/regress/lib/libc/explicit_bzero/explicit_bzero.c197
1 files changed, 0 insertions, 197 deletions
diff --git a/src/regress/lib/libc/explicit_bzero/explicit_bzero.c b/src/regress/lib/libc/explicit_bzero/explicit_bzero.c
deleted file mode 100644
index 34c60baa8a..0000000000
--- a/src/regress/lib/libc/explicit_bzero/explicit_bzero.c
+++ /dev/null
@@ -1,197 +0,0 @@
1/* $OpenBSD: explicit_bzero.c,v 1.6 2014/07/11 01:10:35 matthew Exp $ */
2/*
3 * Copyright (c) 2014 Google Inc.
4 *
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 */
17
18#include <assert.h>
19#include <errno.h>
20#include <signal.h>
21#include <string.h>
22#include <unistd.h>
23
24#define ASSERT_EQ(a, b) assert((a) == (b))
25#define ASSERT_NE(a, b) assert((a) != (b))
26#define ASSERT_GE(a, b) assert((a) >= (b))
27
28/* 128 bits of random data. */
29static const char secret[16] = {
30 0xa0, 0x6c, 0x0c, 0x81, 0xba, 0xd8, 0x5b, 0x0c,
31 0xb0, 0xd6, 0xd4, 0xe3, 0xeb, 0x52, 0x5f, 0x96,
32};
33
34enum {
35 SECRETCOUNT = 64,
36 SECRETBYTES = SECRETCOUNT * sizeof(secret)
37};
38
39static char altstack[SIGSTKSZ + SECRETBYTES];
40
41static void
42setup_stack(void)
43{
44 const stack_t sigstk = {
45 .ss_sp = altstack,
46 .ss_size = sizeof(altstack),
47 };
48
49 ASSERT_EQ(0, sigaltstack(&sigstk, NULL));
50}
51
52static void
53assert_on_stack(void)
54{
55 stack_t cursigstk;
56 ASSERT_EQ(0, sigaltstack(NULL, &cursigstk));
57 ASSERT_EQ(SS_ONSTACK, cursigstk.ss_flags & (SS_DISABLE|SS_ONSTACK));
58}
59
60static void
61call_on_stack(void (*fn)(int))
62{
63 /*
64 * This is a bit more complicated than strictly necessary, but
65 * it ensures we don't have any flaky test failures due to
66 * inherited signal masks/actions/etc.
67 *
68 * On systems where SA_ONSTACK is not supported, this could
69 * alternatively be implemented using makecontext() or
70 * pthread_attr_setstack().
71 */
72
73 const struct sigaction sigact = {
74 .sa_handler = fn,
75 .sa_flags = SA_ONSTACK,
76 };
77 struct sigaction oldsigact;
78 sigset_t sigset, oldsigset;
79
80 /* First, block all signals. */
81 ASSERT_EQ(0, sigemptyset(&sigset));
82 ASSERT_EQ(0, sigfillset(&sigset));
83 ASSERT_EQ(0, sigprocmask(SIG_BLOCK, &sigset, &oldsigset));
84
85 /* Next setup the signal handler for SIGUSR1. */
86 ASSERT_EQ(0, sigaction(SIGUSR1, &sigact, &oldsigact));
87
88 /* Raise SIGUSR1 and momentarily unblock it to run the handler. */
89 ASSERT_EQ(0, raise(SIGUSR1));
90 ASSERT_EQ(0, sigdelset(&sigset, SIGUSR1));
91 ASSERT_EQ(-1, sigsuspend(&sigset));
92 ASSERT_EQ(EINTR, errno);
93
94 /* Restore the original signal action, stack, and mask. */
95 ASSERT_EQ(0, sigaction(SIGUSR1, &oldsigact, NULL));
96 ASSERT_EQ(0, sigprocmask(SIG_SETMASK, &oldsigset, NULL));
97}
98
99static void
100populate_secret(char *buf, size_t len)
101{
102 int i, fds[2];
103 ASSERT_EQ(0, pipe(fds));
104
105 for (i = 0; i < SECRETCOUNT; i++)
106 ASSERT_EQ(sizeof(secret), write(fds[1], secret, sizeof(secret)));
107 ASSERT_EQ(0, close(fds[1]));
108
109 ASSERT_EQ(len, read(fds[0], buf, len));
110 ASSERT_EQ(0, close(fds[0]));
111}
112
113static int
114count_secrets(const char *buf)
115{
116 int res = 0;
117 size_t i;
118 for (i = 0; i < SECRETCOUNT; i++) {
119 if (memcmp(buf + i * sizeof(secret), secret,
120 sizeof(secret)) == 0)
121 res += 1;
122 }
123 return (res);
124}
125
126static char *
127test_without_bzero()
128{
129 char buf[SECRETBYTES];
130 assert_on_stack();
131 populate_secret(buf, sizeof(buf));
132 char *res = memmem(altstack, sizeof(altstack), buf, sizeof(buf));
133 ASSERT_NE(NULL, res);
134 return (res);
135}
136
137static char *
138test_with_bzero()
139{
140 char buf[SECRETBYTES];
141 assert_on_stack();
142 populate_secret(buf, sizeof(buf));
143 char *res = memmem(altstack, sizeof(altstack), buf, sizeof(buf));
144 ASSERT_NE(NULL, res);
145 explicit_bzero(buf, sizeof(buf));
146 return (res);
147}
148
149static void
150do_test_without_bzero(int signo)
151{
152 char *buf = test_without_bzero();
153 ASSERT_GE(count_secrets(buf), 1);
154}
155
156static void
157do_test_with_bzero(int signo)
158{
159 char *buf = test_with_bzero();
160 ASSERT_EQ(count_secrets(buf), 0);
161}
162
163int
164main()
165{
166 setup_stack();
167
168 /*
169 * Solaris and OS X clobber the signal stack after returning to the
170 * normal stack, so we need to inspect altstack while we're still
171 * running on it. Unfortunately, this means we risk clobbering the
172 * buffer ourselves.
173 *
174 * To minimize this risk, test_with{,out}_bzero() are responsible for
175 * locating the offset of their buf variable within altstack, and
176 * and returning that address. Then we can simply memcmp() repeatedly
177 * to count how many instances of secret we found.
178 */
179
180 /*
181 * First, test that if we *don't* call explicit_bzero, that we
182 * *are* able to find at least one instance of the secret data still
183 * on the stack. This sanity checks that call_on_stack() and
184 * populate_secret() work as intended.
185 */
186 memset(altstack, 0, sizeof(altstack));
187 call_on_stack(do_test_without_bzero);
188
189 /*
190 * Now test with a call to explicit_bzero() and check that we
191 * *don't* find any instances of the secret data.
192 */
193 memset(altstack, 0, sizeof(altstack));
194 call_on_stack(do_test_with_bzero);
195
196 return (0);
197}
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