constant_time_test.c revision 279265
1/* crypto/constant_time_test.c */
2/*
3 * Utilities for constant-time cryptography.
4 *
5 * Author: Emilia Kasper (emilia@openssl.org)
6 * Based on previous work by Bodo Moeller, Emilia Kasper, Adam Langley
7 * (Google).
8 * ====================================================================
9 * Copyright (c) 2014 The OpenSSL Project.  All rights reserved.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the copyright
15 *    notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 *    notice, this list of conditions and the following disclaimer in the
18 *    documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 *    must display the following acknowledgement:
21 *    "This product includes cryptographic software written by
22 *     Eric Young (eay@cryptsoft.com)"
23 *    The word 'cryptographic' can be left out if the rouines from the library
24 *    being used are not cryptographic related :-).
25 * 4. If you include any Windows specific code (or a derivative thereof) from
26 *    the apps directory (application code) you must include an acknowledgement:
27 *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
28 *
29 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
30 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
31 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
32 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
33 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
34 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
35 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
36 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
37 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
38 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
39 * SUCH DAMAGE.
40 *
41 * The licence and distribution terms for any publically available version or
42 * derivative of this code cannot be changed.  i.e. this code cannot simply be
43 * copied and put under another distribution licence
44 * [including the GNU Public Licence.]
45 */
46
47#include "../crypto/constant_time_locl.h"
48
49#include <limits.h>
50#include <stdio.h>
51#include <stdlib.h>
52
53static const unsigned int CONSTTIME_TRUE = (unsigned)(~0);
54static const unsigned int CONSTTIME_FALSE = 0;
55static const unsigned char CONSTTIME_TRUE_8 = 0xff;
56static const unsigned char CONSTTIME_FALSE_8 = 0;
57
58static int test_binary_op(unsigned int (*op)(unsigned int a, unsigned int b),
59	const char* op_name, unsigned int a, unsigned int b, int is_true)
60	{
61	unsigned c = op(a, b);
62	if (is_true && c != CONSTTIME_TRUE)
63		{
64		fprintf(stderr, "Test failed for %s(%du, %du): expected %du "
65			"(TRUE), got %du\n", op_name, a, b, CONSTTIME_TRUE, c);
66		return 1;
67		}
68	else if (!is_true && c != CONSTTIME_FALSE)
69		{
70		fprintf(stderr, "Test failed for  %s(%du, %du): expected %du "
71			"(FALSE), got %du\n", op_name, a, b, CONSTTIME_FALSE,
72			c);
73		return 1;
74		}
75        return 0;
76	}
77
78static int test_binary_op_8(unsigned char (*op)(unsigned int a, unsigned int b),
79	const char* op_name, unsigned int a, unsigned int b, int is_true)
80	{
81	unsigned char c = op(a, b);
82	if (is_true && c != CONSTTIME_TRUE_8)
83		{
84		fprintf(stderr, "Test failed for %s(%du, %du): expected %u "
85			"(TRUE), got %u\n", op_name, a, b, CONSTTIME_TRUE_8, c);
86		return 1;
87		}
88	else if (!is_true && c != CONSTTIME_FALSE_8)
89		{
90		fprintf(stderr, "Test failed for  %s(%du, %du): expected %u "
91			"(FALSE), got %u\n", op_name, a, b, CONSTTIME_FALSE_8,
92			c);
93		return 1;
94		}
95        return 0;
96	}
97
98static int test_is_zero(unsigned int a)
99	{
100	unsigned int c = constant_time_is_zero(a);
101	if (a == 0 && c != CONSTTIME_TRUE)
102		{
103		fprintf(stderr, "Test failed for constant_time_is_zero(%du): "
104			"expected %du (TRUE), got %du\n", a, CONSTTIME_TRUE, c);
105		return 1;
106		}
107	else if (a != 0 && c != CONSTTIME_FALSE)
108		{
109		fprintf(stderr, "Test failed for constant_time_is_zero(%du): "
110			"expected %du (FALSE), got %du\n", a, CONSTTIME_FALSE,
111			c);
112		return 1;
113		}
114        return 0;
115	}
116
117static int test_is_zero_8(unsigned int a)
118	{
119	unsigned char c = constant_time_is_zero_8(a);
120	if (a == 0 && c != CONSTTIME_TRUE_8)
121		{
122		fprintf(stderr, "Test failed for constant_time_is_zero(%du): "
123			"expected %u (TRUE), got %u\n", a, CONSTTIME_TRUE_8, c);
124		return 1;
125		}
126	else if (a != 0 && c != CONSTTIME_FALSE)
127		{
128		fprintf(stderr, "Test failed for constant_time_is_zero(%du): "
129			"expected %u (FALSE), got %u\n", a, CONSTTIME_FALSE_8,
130			c);
131		return 1;
132		}
133        return 0;
134	}
135
136static int test_select(unsigned int a, unsigned int b)
137	{
138	unsigned int selected = constant_time_select(CONSTTIME_TRUE, a, b);
139	if (selected != a)
140		{
141		fprintf(stderr, "Test failed for constant_time_select(%du, %du,"
142			"%du): expected %du(first value), got %du\n",
143			CONSTTIME_TRUE, a, b, a, selected);
144		return 1;
145		}
146	selected = constant_time_select(CONSTTIME_FALSE, a, b);
147	if (selected != b)
148		{
149		fprintf(stderr, "Test failed for constant_time_select(%du, %du,"
150			"%du): expected %du(second value), got %du\n",
151			CONSTTIME_FALSE, a, b, b, selected);
152		return 1;
153		}
154	return 0;
155	}
156
157static int test_select_8(unsigned char a, unsigned char b)
158	{
159	unsigned char selected = constant_time_select_8(CONSTTIME_TRUE_8, a, b);
160	if (selected != a)
161		{
162		fprintf(stderr, "Test failed for constant_time_select(%u, %u,"
163			"%u): expected %u(first value), got %u\n",
164			CONSTTIME_TRUE, a, b, a, selected);
165		return 1;
166		}
167	selected = constant_time_select_8(CONSTTIME_FALSE_8, a, b);
168	if (selected != b)
169		{
170		fprintf(stderr, "Test failed for constant_time_select(%u, %u,"
171			"%u): expected %u(second value), got %u\n",
172			CONSTTIME_FALSE, a, b, b, selected);
173		return 1;
174		}
175	return 0;
176	}
177
178static int test_select_int(int a, int b)
179	{
180	int selected = constant_time_select_int(CONSTTIME_TRUE, a, b);
181	if (selected != a)
182		{
183		fprintf(stderr, "Test failed for constant_time_select(%du, %d,"
184			"%d): expected %d(first value), got %d\n",
185			CONSTTIME_TRUE, a, b, a, selected);
186		return 1;
187		}
188	selected = constant_time_select_int(CONSTTIME_FALSE, a, b);
189	if (selected != b)
190		{
191		fprintf(stderr, "Test failed for constant_time_select(%du, %d,"
192			"%d): expected %d(second value), got %d\n",
193			CONSTTIME_FALSE, a, b, b, selected);
194		return 1;
195		}
196	return 0;
197	}
198
199static int test_eq_int(int a, int b)
200	{
201	unsigned int equal = constant_time_eq_int(a, b);
202	if (a == b && equal != CONSTTIME_TRUE)
203		{
204		fprintf(stderr, "Test failed for constant_time_eq_int(%d, %d): "
205			"expected %du(TRUE), got %du\n",
206			a, b, CONSTTIME_TRUE, equal);
207		return 1;
208		}
209	else if (a != b && equal != CONSTTIME_FALSE)
210		{
211		fprintf(stderr, "Test failed for constant_time_eq_int(%d, %d): "
212			"expected %du(FALSE), got %du\n",
213			a, b, CONSTTIME_FALSE, equal);
214		return 1;
215		}
216	return 0;
217	}
218
219static int test_eq_int_8(int a, int b)
220	{
221	unsigned char equal = constant_time_eq_int_8(a, b);
222	if (a == b && equal != CONSTTIME_TRUE_8)
223		{
224		fprintf(stderr, "Test failed for constant_time_eq_int_8(%d, %d): "
225			"expected %u(TRUE), got %u\n",
226			a, b, CONSTTIME_TRUE_8, equal);
227		return 1;
228		}
229	else if (a != b && equal != CONSTTIME_FALSE_8)
230		{
231		fprintf(stderr, "Test failed for constant_time_eq_int_8(%d, %d): "
232			"expected %u(FALSE), got %u\n",
233			a, b, CONSTTIME_FALSE_8, equal);
234		return 1;
235		}
236	return 0;
237	}
238
239static unsigned int test_values[] = {0, 1, 1024, 12345, 32000, UINT_MAX/2-1,
240                                     UINT_MAX/2, UINT_MAX/2+1, UINT_MAX-1,
241                                     UINT_MAX};
242
243static unsigned char test_values_8[] = {0, 1, 2, 20, 32, 127, 128, 129, 255};
244
245static int signed_test_values[] = {0, 1, -1, 1024, -1024, 12345, -12345,
246				   32000, -32000, INT_MAX, INT_MIN, INT_MAX-1,
247				   INT_MIN+1};
248
249
250int main(int argc, char *argv[])
251	{
252	unsigned int a, b, i, j;
253	int c, d;
254	unsigned char e, f;
255	int num_failed = 0, num_all = 0;
256	fprintf(stdout, "Testing constant time operations...\n");
257
258	for (i = 0; i < sizeof(test_values)/sizeof(int); ++i)
259		{
260		a = test_values[i];
261		num_failed += test_is_zero(a);
262		num_failed += test_is_zero_8(a);
263		num_all += 2;
264		for (j = 0; j < sizeof(test_values)/sizeof(int); ++j)
265			{
266			b = test_values[j];
267			num_failed += test_binary_op(&constant_time_lt,
268				"constant_time_lt", a, b, a < b);
269			num_failed += test_binary_op_8(&constant_time_lt_8,
270				"constant_time_lt_8", a, b, a < b);
271			num_failed += test_binary_op(&constant_time_lt,
272				"constant_time_lt_8", b, a, b < a);
273			num_failed += test_binary_op_8(&constant_time_lt_8,
274				"constant_time_lt_8", b, a, b < a);
275			num_failed += test_binary_op(&constant_time_ge,
276				"constant_time_ge", a, b, a >= b);
277			num_failed += test_binary_op_8(&constant_time_ge_8,
278				"constant_time_ge_8", a, b, a >= b);
279			num_failed += test_binary_op(&constant_time_ge,
280				"constant_time_ge", b, a, b >= a);
281			num_failed += test_binary_op_8(&constant_time_ge_8,
282				"constant_time_ge_8", b, a, b >= a);
283			num_failed += test_binary_op(&constant_time_eq,
284				"constant_time_eq", a, b, a == b);
285			num_failed += test_binary_op_8(&constant_time_eq_8,
286				"constant_time_eq_8", a, b, a == b);
287			num_failed += test_binary_op(&constant_time_eq,
288				"constant_time_eq", b, a, b == a);
289			num_failed += test_binary_op_8(&constant_time_eq_8,
290				"constant_time_eq_8", b, a, b == a);
291			num_failed += test_select(a, b);
292			num_all += 13;
293			}
294		}
295
296	for (i = 0; i < sizeof(signed_test_values)/sizeof(int); ++i)
297		{
298		c = signed_test_values[i];
299		for (j = 0; j < sizeof(signed_test_values)/sizeof(int); ++j)
300			{
301			d = signed_test_values[j];
302			num_failed += test_select_int(c, d);
303			num_failed += test_eq_int(c, d);
304			num_failed += test_eq_int_8(c, d);
305			num_all += 3;
306			}
307		}
308
309	for (i = 0; i < sizeof(test_values_8); ++i)
310		{
311		e = test_values_8[i];
312		for (j = 0; j < sizeof(test_values_8); ++j)
313			{
314			f = test_values_8[j];
315			num_failed += test_select_8(e, f);
316			num_all += 1;
317			}
318		}
319
320	if (!num_failed)
321		{
322		fprintf(stdout, "ok (ran %d tests)\n", num_all);
323		return EXIT_SUCCESS;
324		}
325	else
326		{
327		fprintf(stdout, "%d of %d tests failed!\n", num_failed, num_all);
328		return EXIT_FAILURE;
329		}
330	}
331