crypto/constant_time_test.c

   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
  53 static const unsigned int CONSTTIME_TRUE = ~0;
  54 static const unsigned int CONSTTIME_FALSE = 0;
  55 static const unsigned char CONSTTIME_TRUE_8 = ~0;
  56 static const unsigned char CONSTTIME_FALSE_8 = 0;
  57
  58 static 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
  78 static 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
  98 static 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
 117 static 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
 136 static unsigned int test_values[] = {0, 1, 1024, 12345, 32000, UINT_MAX/2-1,
 137                                      UINT_MAX/2, UINT_MAX/2+1, UINT_MAX-1,
 138                                      UINT_MAX};
 139
 140 int main(int argc, char *argv[])
 141         {
 142         unsigned int a, b, i, j;
 143         int num_failed = 0, num_all = 0;
 144         fprintf(stdout, "Testing constant time operations...\n");
 145
 146         for (i = 0; i < sizeof(test_values)/sizeof(int); ++i)
 147                 {
 148                 a = test_values[i];
 149                 num_failed += test_is_zero(a);
 150                 num_failed += test_is_zero_8(a);
 151                 num_failed += test_binary_op(&constant_time_lt,
 152                         "constant_time_lt", a, a, 0);
 153                 num_failed += test_binary_op_8(&constant_time_lt_8,
 154                         "constant_time_lt_8", a, a, 0);
 155                 num_failed += test_binary_op(&constant_time_ge,
 156                         "constant_time_ge", a, a, 1);
 157                 num_failed += test_binary_op_8(&constant_time_ge_8,
 158                         "constant_time_ge_8", a, a, 1);
 159                 num_failed += test_binary_op(&constant_time_eq,
 160                         "constant_time_eq", a, a, 1);
 161                 num_failed += test_binary_op_8(&constant_time_eq_8,
 162                         "constant_time_eq_8", a, a, 1);
 163                 num_all += 8;
 164                 for (j = i + 1; j < sizeof(test_values)/sizeof(int); ++j)
 165                         {
 166                         b = test_values[j];
 167                         num_failed += test_binary_op(&constant_time_lt,
 168                                 "constant_time_lt", a, b, a < b);
 169                         num_failed += test_binary_op_8(&constant_time_lt_8,
 170                                 "constant_time_lt_8", a, b, a < b);
 171                         num_failed += test_binary_op(&constant_time_lt,
 172                                 "constant_time_lt_8", b, a, b < a);
 173                         num_failed += test_binary_op_8(&constant_time_lt_8,
 174                                 "constant_time_lt_8", b, a, b < a);
 175                         num_failed += test_binary_op(&constant_time_ge,
 176                                 "constant_time_ge", a, b, a >= b);
 177                         num_failed += test_binary_op_8(&constant_time_ge_8,
 178                                 "constant_time_ge_8", a, b, a >= b);
 179                         num_failed += test_binary_op(&constant_time_ge,
 180                                 "constant_time_ge", b, a, b >= a);
 181                         num_failed += test_binary_op_8(&constant_time_ge_8,
 182                                 "constant_time_ge_8", b, a, b >= a);
 183                         num_failed += test_binary_op(&constant_time_eq,
 184                                 "constant_time_eq", a, b, a == b);
 185                         num_failed += test_binary_op_8(&constant_time_eq_8,
 186                                 "constant_time_eq_8", a, b, a == b);
 187                         num_failed += test_binary_op(&constant_time_eq,
 188                                 "constant_time_eq", b, a, b == a);
 189                         num_failed += test_binary_op_8(&constant_time_eq_8,
 190                                 "constant_time_eq_8", b, a, b == a);
 191                         num_all += 12;
 192                         }
 193                 }
 194
 195         if (!num_failed)
 196                 {
 197                 fprintf(stdout, "ok (ran %d tests)\n", num_all);
 198                 return EXIT_SUCCESS;
 199                 }
 200         else
 201                 {
 202                 fprintf(stdout, "%d of %d tests failed!\n", num_failed, num_all);
 203                 return EXIT_FAILURE;
 204                 }
 205         }