constant_time_test.c revision 296465
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, 60 int is_true) 61{ 62 unsigned c = op(a, b); 63 if (is_true && c != CONSTTIME_TRUE) { 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 } else if (!is_true && c != CONSTTIME_FALSE) { 68 fprintf(stderr, "Test failed for %s(%du, %du): expected %du " 69 "(FALSE), got %du\n", op_name, a, b, CONSTTIME_FALSE, c); 70 return 1; 71 } 72 return 0; 73} 74 75static int test_binary_op_8(unsigned 76 char (*op) (unsigned int a, unsigned int b), 77 const char *op_name, unsigned int a, 78 unsigned int b, int is_true) 79{ 80 unsigned char c = op(a, b); 81 if (is_true && c != CONSTTIME_TRUE_8) { 82 fprintf(stderr, "Test failed for %s(%du, %du): expected %u " 83 "(TRUE), got %u\n", op_name, a, b, CONSTTIME_TRUE_8, c); 84 return 1; 85 } else if (!is_true && c != CONSTTIME_FALSE_8) { 86 fprintf(stderr, "Test failed for %s(%du, %du): expected %u " 87 "(FALSE), got %u\n", op_name, a, b, CONSTTIME_FALSE_8, c); 88 return 1; 89 } 90 return 0; 91} 92 93static int test_is_zero(unsigned int a) 94{ 95 unsigned int c = constant_time_is_zero(a); 96 if (a == 0 && c != CONSTTIME_TRUE) { 97 fprintf(stderr, "Test failed for constant_time_is_zero(%du): " 98 "expected %du (TRUE), got %du\n", a, CONSTTIME_TRUE, c); 99 return 1; 100 } else if (a != 0 && c != CONSTTIME_FALSE) { 101 fprintf(stderr, "Test failed for constant_time_is_zero(%du): " 102 "expected %du (FALSE), got %du\n", a, CONSTTIME_FALSE, c); 103 return 1; 104 } 105 return 0; 106} 107 108static int test_is_zero_8(unsigned int a) 109{ 110 unsigned char c = constant_time_is_zero_8(a); 111 if (a == 0 && c != CONSTTIME_TRUE_8) { 112 fprintf(stderr, "Test failed for constant_time_is_zero(%du): " 113 "expected %u (TRUE), got %u\n", a, CONSTTIME_TRUE_8, c); 114 return 1; 115 } else if (a != 0 && c != CONSTTIME_FALSE) { 116 fprintf(stderr, "Test failed for constant_time_is_zero(%du): " 117 "expected %u (FALSE), got %u\n", a, CONSTTIME_FALSE_8, c); 118 return 1; 119 } 120 return 0; 121} 122 123static int test_select(unsigned int a, unsigned int b) 124{ 125 unsigned int selected = constant_time_select(CONSTTIME_TRUE, a, b); 126 if (selected != a) { 127 fprintf(stderr, "Test failed for constant_time_select(%du, %du," 128 "%du): expected %du(first value), got %du\n", 129 CONSTTIME_TRUE, a, b, a, selected); 130 return 1; 131 } 132 selected = constant_time_select(CONSTTIME_FALSE, a, b); 133 if (selected != b) { 134 fprintf(stderr, "Test failed for constant_time_select(%du, %du," 135 "%du): expected %du(second value), got %du\n", 136 CONSTTIME_FALSE, a, b, b, selected); 137 return 1; 138 } 139 return 0; 140} 141 142static int test_select_8(unsigned char a, unsigned char b) 143{ 144 unsigned char selected = constant_time_select_8(CONSTTIME_TRUE_8, a, b); 145 if (selected != a) { 146 fprintf(stderr, "Test failed for constant_time_select(%u, %u," 147 "%u): expected %u(first value), got %u\n", 148 CONSTTIME_TRUE, a, b, a, selected); 149 return 1; 150 } 151 selected = constant_time_select_8(CONSTTIME_FALSE_8, a, b); 152 if (selected != b) { 153 fprintf(stderr, "Test failed for constant_time_select(%u, %u," 154 "%u): expected %u(second value), got %u\n", 155 CONSTTIME_FALSE, a, b, b, selected); 156 return 1; 157 } 158 return 0; 159} 160 161static int test_select_int(int a, int b) 162{ 163 int selected = constant_time_select_int(CONSTTIME_TRUE, a, b); 164 if (selected != a) { 165 fprintf(stderr, "Test failed for constant_time_select(%du, %d," 166 "%d): expected %d(first value), got %d\n", 167 CONSTTIME_TRUE, a, b, a, selected); 168 return 1; 169 } 170 selected = constant_time_select_int(CONSTTIME_FALSE, a, b); 171 if (selected != b) { 172 fprintf(stderr, "Test failed for constant_time_select(%du, %d," 173 "%d): expected %d(second value), got %d\n", 174 CONSTTIME_FALSE, a, b, b, selected); 175 return 1; 176 } 177 return 0; 178} 179 180static int test_eq_int(int a, int b) 181{ 182 unsigned int equal = constant_time_eq_int(a, b); 183 if (a == b && equal != CONSTTIME_TRUE) { 184 fprintf(stderr, "Test failed for constant_time_eq_int(%d, %d): " 185 "expected %du(TRUE), got %du\n", a, b, CONSTTIME_TRUE, equal); 186 return 1; 187 } else if (a != b && equal != CONSTTIME_FALSE) { 188 fprintf(stderr, "Test failed for constant_time_eq_int(%d, %d): " 189 "expected %du(FALSE), got %du\n", 190 a, b, CONSTTIME_FALSE, equal); 191 return 1; 192 } 193 return 0; 194} 195 196static int test_eq_int_8(int a, int b) 197{ 198 unsigned char equal = constant_time_eq_int_8(a, b); 199 if (a == b && equal != CONSTTIME_TRUE_8) { 200 fprintf(stderr, "Test failed for constant_time_eq_int_8(%d, %d): " 201 "expected %u(TRUE), got %u\n", a, b, CONSTTIME_TRUE_8, equal); 202 return 1; 203 } else if (a != b && equal != CONSTTIME_FALSE_8) { 204 fprintf(stderr, "Test failed for constant_time_eq_int_8(%d, %d): " 205 "expected %u(FALSE), got %u\n", 206 a, b, CONSTTIME_FALSE_8, equal); 207 return 1; 208 } 209 return 0; 210} 211 212static unsigned int test_values[] = 213 { 0, 1, 1024, 12345, 32000, UINT_MAX / 2 - 1, 214 UINT_MAX / 2, UINT_MAX / 2 + 1, UINT_MAX - 1, 215 UINT_MAX 216}; 217 218static unsigned char test_values_8[] = 219 { 0, 1, 2, 20, 32, 127, 128, 129, 255 }; 220 221static int signed_test_values[] = { 0, 1, -1, 1024, -1024, 12345, -12345, 222 32000, -32000, INT_MAX, INT_MIN, INT_MAX - 1, 223 INT_MIN + 1 224}; 225 226int main(int argc, char *argv[]) 227{ 228 unsigned int a, b, i, j; 229 int c, d; 230 unsigned char e, f; 231 int num_failed = 0, num_all = 0; 232 fprintf(stdout, "Testing constant time operations...\n"); 233 234 for (i = 0; i < sizeof(test_values) / sizeof(int); ++i) { 235 a = test_values[i]; 236 num_failed += test_is_zero(a); 237 num_failed += test_is_zero_8(a); 238 num_all += 2; 239 for (j = 0; j < sizeof(test_values) / sizeof(int); ++j) { 240 b = test_values[j]; 241 num_failed += test_binary_op(&constant_time_lt, 242 "constant_time_lt", a, b, a < b); 243 num_failed += test_binary_op_8(&constant_time_lt_8, 244 "constant_time_lt_8", a, b, a < b); 245 num_failed += test_binary_op(&constant_time_lt, 246 "constant_time_lt_8", b, a, b < a); 247 num_failed += test_binary_op_8(&constant_time_lt_8, 248 "constant_time_lt_8", b, a, b < a); 249 num_failed += test_binary_op(&constant_time_ge, 250 "constant_time_ge", a, b, a >= b); 251 num_failed += test_binary_op_8(&constant_time_ge_8, 252 "constant_time_ge_8", a, b, 253 a >= b); 254 num_failed += 255 test_binary_op(&constant_time_ge, "constant_time_ge", b, a, 256 b >= a); 257 num_failed += 258 test_binary_op_8(&constant_time_ge_8, "constant_time_ge_8", b, 259 a, b >= a); 260 num_failed += 261 test_binary_op(&constant_time_eq, "constant_time_eq", a, b, 262 a == b); 263 num_failed += 264 test_binary_op_8(&constant_time_eq_8, "constant_time_eq_8", a, 265 b, a == b); 266 num_failed += 267 test_binary_op(&constant_time_eq, "constant_time_eq", b, a, 268 b == a); 269 num_failed += 270 test_binary_op_8(&constant_time_eq_8, "constant_time_eq_8", b, 271 a, b == a); 272 num_failed += test_select(a, b); 273 num_all += 13; 274 } 275 } 276 277 for (i = 0; i < sizeof(signed_test_values) / sizeof(int); ++i) { 278 c = signed_test_values[i]; 279 for (j = 0; j < sizeof(signed_test_values) / sizeof(int); ++j) { 280 d = signed_test_values[j]; 281 num_failed += test_select_int(c, d); 282 num_failed += test_eq_int(c, d); 283 num_failed += test_eq_int_8(c, d); 284 num_all += 3; 285 } 286 } 287 288 for (i = 0; i < sizeof(test_values_8); ++i) { 289 e = test_values_8[i]; 290 for (j = 0; j < sizeof(test_values_8); ++j) { 291 f = test_values_8[j]; 292 num_failed += test_select_8(e, f); 293 num_all += 1; 294 } 295 } 296 297 if (!num_failed) { 298 fprintf(stdout, "ok (ran %d tests)\n", num_all); 299 return EXIT_SUCCESS; 300 } else { 301 fprintf(stdout, "%d of %d tests failed!\n", num_failed, num_all); 302 return EXIT_FAILURE; 303 } 304} 305