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