| /* |
| * Utilities for constant-time cryptography. |
| * |
| * Author: Emilia Kasper (emilia@openssl.org) |
| * Based on previous work by Bodo Moeller, Emilia Kasper, Adam Langley |
| * (Google). |
| * ==================================================================== |
| * Copyright (c) 2014 The OpenSSL Project. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * 3. All advertising materials mentioning features or use of this software |
| * must display the following acknowledgement: |
| * "This product includes cryptographic software written by |
| * Eric Young (eay@cryptsoft.com)" |
| * The word 'cryptographic' can be left out if the rouines from the library |
| * being used are not cryptographic related :-). |
| * 4. If you include any Windows specific code (or a derivative thereof) from |
| * the apps directory (application code) you must include an acknowledgement: |
| * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" |
| * |
| * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND |
| * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE |
| * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| * |
| * The licence and distribution terms for any publically available version or |
| * derivative of this code cannot be changed. i.e. this code cannot simply be |
| * copied and put under another distribution licence |
| * [including the GNU Public Licence.] |
| */ |
| |
| #include "internal.h" |
| |
| #include <limits.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| |
| |
| static const unsigned int CONSTTIME_TRUE = (unsigned)(~0); |
| static const unsigned int CONSTTIME_FALSE = 0; |
| static const uint8_t CONSTTIME_TRUE_8 = 0xff; |
| static const uint8_t CONSTTIME_FALSE_8 = 0; |
| |
| static int test_binary_op(unsigned int (*op)(unsigned int a, unsigned int b), |
| const char* op_name, unsigned int a, unsigned int b, |
| int is_true) { |
| unsigned c = op(a, b); |
| if (is_true && c != CONSTTIME_TRUE) { |
| fprintf(stderr, |
| "Test failed for %s(%du, %du): expected %du (TRUE), got %du\n", |
| op_name, a, b, CONSTTIME_TRUE, c); |
| return 1; |
| } else if (!is_true && c != CONSTTIME_FALSE) { |
| fprintf(stderr, |
| "Test failed for %s(%du, %du): expected %du (FALSE), got %du\n", |
| op_name, a, b, CONSTTIME_FALSE, c); |
| return 1; |
| } |
| return 0; |
| } |
| |
| static int test_binary_op_8(uint8_t (*op)(unsigned int a, unsigned int b), |
| const char* op_name, unsigned int a, unsigned int b, |
| int is_true) { |
| uint8_t c = op(a, b); |
| if (is_true && c != CONSTTIME_TRUE_8) { |
| fprintf(stderr, |
| "Test failed for %s(%du, %du): expected %u (TRUE), got %u\n", |
| op_name, a, b, CONSTTIME_TRUE_8, c); |
| return 1; |
| } else if (!is_true && c != CONSTTIME_FALSE_8) { |
| fprintf(stderr, |
| "Test failed for %s(%du, %du): expected %u (FALSE), got %u\n", |
| op_name, a, b, CONSTTIME_FALSE_8, c); |
| return 1; |
| } |
| return 0; |
| } |
| |
| static int test_is_zero(unsigned int a) { |
| unsigned int c = constant_time_is_zero(a); |
| if (a == 0 && c != CONSTTIME_TRUE) { |
| fprintf(stderr, |
| "Test failed for constant_time_is_zero(%du): expected %du (TRUE), " |
| "got %du\n", |
| a, CONSTTIME_TRUE, c); |
| return 1; |
| } else if (a != 0 && c != CONSTTIME_FALSE) { |
| fprintf(stderr, |
| "Test failed for constant_time_is_zero(%du): expected %du (FALSE), " |
| "got %du\n", |
| a, CONSTTIME_FALSE, c); |
| return 1; |
| } |
| return 0; |
| } |
| |
| static int test_is_zero_8(unsigned int a) { |
| uint8_t c = constant_time_is_zero_8(a); |
| if (a == 0 && c != CONSTTIME_TRUE_8) { |
| fprintf(stderr, |
| "Test failed for constant_time_is_zero(%du): expected %u (TRUE), " |
| "got %u\n", |
| a, CONSTTIME_TRUE_8, c); |
| return 1; |
| } else if (a != 0 && c != CONSTTIME_FALSE) { |
| fprintf(stderr, |
| "Test failed for constant_time_is_zero(%du): expected %u (FALSE), " |
| "got %u\n", |
| a, CONSTTIME_FALSE_8, c); |
| return 1; |
| } |
| return 0; |
| } |
| |
| static int test_select(unsigned int a, unsigned int b) { |
| unsigned int selected = constant_time_select(CONSTTIME_TRUE, a, b); |
| if (selected != a) { |
| fprintf(stderr, |
| "Test failed for constant_time_select(%du, %du," |
| "%du): expected %du(first value), got %du\n", |
| CONSTTIME_TRUE, a, b, a, selected); |
| return 1; |
| } |
| selected = constant_time_select(CONSTTIME_FALSE, a, b); |
| if (selected != b) { |
| fprintf(stderr, |
| "Test failed for constant_time_select(%du, %du," |
| "%du): expected %du(second value), got %du\n", |
| CONSTTIME_FALSE, a, b, b, selected); |
| return 1; |
| } |
| return 0; |
| } |
| |
| static int test_select_8(uint8_t a, uint8_t b) { |
| uint8_t selected = constant_time_select_8(CONSTTIME_TRUE_8, a, b); |
| if (selected != a) { |
| fprintf(stderr, |
| "Test failed for constant_time_select(%u, %u," |
| "%u): expected %u(first value), got %u\n", |
| CONSTTIME_TRUE, a, b, a, selected); |
| return 1; |
| } |
| selected = constant_time_select_8(CONSTTIME_FALSE_8, a, b); |
| if (selected != b) { |
| fprintf(stderr, |
| "Test failed for constant_time_select(%u, %u," |
| "%u): expected %u(second value), got %u\n", |
| CONSTTIME_FALSE, a, b, b, selected); |
| return 1; |
| } |
| return 0; |
| } |
| |
| static int test_select_int(int a, int b) { |
| int selected = constant_time_select_int(CONSTTIME_TRUE, a, b); |
| if (selected != a) { |
| fprintf(stderr, |
| "Test failed for constant_time_select(%du, %d," |
| "%d): expected %d(first value), got %d\n", |
| CONSTTIME_TRUE, a, b, a, selected); |
| return 1; |
| } |
| selected = constant_time_select_int(CONSTTIME_FALSE, a, b); |
| if (selected != b) { |
| fprintf(stderr, |
| "Test failed for constant_time_select(%du, %d," |
| "%d): expected %d(second value), got %d\n", |
| CONSTTIME_FALSE, a, b, b, selected); |
| return 1; |
| } |
| return 0; |
| } |
| |
| static int test_eq_int(int a, int b) { |
| unsigned int equal = constant_time_eq_int(a, b); |
| if (a == b && equal != CONSTTIME_TRUE) { |
| fprintf(stderr, |
| "Test failed for constant_time_eq_int(%d, %d): expected %du(TRUE), " |
| "got %du\n", |
| a, b, CONSTTIME_TRUE, equal); |
| return 1; |
| } else if (a != b && equal != CONSTTIME_FALSE) { |
| fprintf(stderr, |
| "Test failed for constant_time_eq_int(%d, %d): expected " |
| "%du(FALSE), got %du\n", |
| a, b, CONSTTIME_FALSE, equal); |
| return 1; |
| } |
| return 0; |
| } |
| |
| static int test_eq_int_8(int a, int b) { |
| uint8_t equal = constant_time_eq_int_8(a, b); |
| if (a == b && equal != CONSTTIME_TRUE_8) { |
| fprintf(stderr, |
| "Test failed for constant_time_eq_int_8(%d, %d): expected " |
| "%u(TRUE), got %u\n", |
| a, b, CONSTTIME_TRUE_8, equal); |
| return 1; |
| } else if (a != b && equal != CONSTTIME_FALSE_8) { |
| fprintf(stderr, |
| "Test failed for constant_time_eq_int_8(%d, %d): expected " |
| "%u(FALSE), got %u\n", |
| a, b, CONSTTIME_FALSE_8, equal); |
| return 1; |
| } |
| return 0; |
| } |
| |
| static unsigned int test_values[] = {0, 1, 1024, 12345, 32000, UINT_MAX / 2 - 1, |
| UINT_MAX / 2, UINT_MAX / 2 + 1, |
| UINT_MAX - 1, UINT_MAX}; |
| |
| static uint8_t test_values_8[] = {0, 1, 2, 20, 32, 127, 128, 129, 255}; |
| |
| static int signed_test_values[] = { |
| 0, 1, -1, 1024, -1024, 12345, -12345, |
| 32000, -32000, INT_MAX, INT_MIN, INT_MAX - 1, INT_MIN + 1}; |
| |
| int main(int argc, char* argv[]) { |
| unsigned int a, b, i, j; |
| int c, d; |
| uint8_t e, f; |
| int num_failed = 0, num_all = 0; |
| fprintf(stdout, "Testing constant time operations...\n"); |
| |
| for (i = 0; i < sizeof(test_values) / sizeof(int); ++i) { |
| a = test_values[i]; |
| num_failed += test_is_zero(a); |
| num_failed += test_is_zero_8(a); |
| num_all += 2; |
| for (j = 0; j < sizeof(test_values) / sizeof(int); ++j) { |
| b = test_values[j]; |
| num_failed += |
| test_binary_op(&constant_time_lt, "constant_time_lt", a, b, a < b); |
| num_failed += test_binary_op_8(&constant_time_lt_8, "constant_time_lt_8", |
| a, b, a < b); |
| num_failed += |
| test_binary_op(&constant_time_lt, "constant_time_lt_8", b, a, b < a); |
| num_failed += test_binary_op_8(&constant_time_lt_8, "constant_time_lt_8", |
| b, a, b < a); |
| num_failed += |
| test_binary_op(&constant_time_ge, "constant_time_ge", a, b, a >= b); |
| num_failed += test_binary_op_8(&constant_time_ge_8, "constant_time_ge_8", |
| a, b, a >= b); |
| num_failed += |
| test_binary_op(&constant_time_ge, "constant_time_ge", b, a, b >= a); |
| num_failed += test_binary_op_8(&constant_time_ge_8, "constant_time_ge_8", |
| b, a, b >= a); |
| num_failed += |
| test_binary_op(&constant_time_eq, "constant_time_eq", a, b, a == b); |
| num_failed += test_binary_op_8(&constant_time_eq_8, "constant_time_eq_8", |
| a, b, a == b); |
| num_failed += |
| test_binary_op(&constant_time_eq, "constant_time_eq", b, a, b == a); |
| num_failed += test_binary_op_8(&constant_time_eq_8, "constant_time_eq_8", |
| b, a, b == a); |
| num_failed += test_select(a, b); |
| num_all += 13; |
| } |
| } |
| |
| for (i = 0; i < sizeof(signed_test_values) / sizeof(int); ++i) { |
| c = signed_test_values[i]; |
| for (j = 0; j < sizeof(signed_test_values) / sizeof(int); ++j) { |
| d = signed_test_values[j]; |
| num_failed += test_select_int(c, d); |
| num_failed += test_eq_int(c, d); |
| num_failed += test_eq_int_8(c, d); |
| num_all += 3; |
| } |
| } |
| |
| for (i = 0; i < sizeof(test_values_8); ++i) { |
| e = test_values_8[i]; |
| for (j = 0; j < sizeof(test_values_8); ++j) { |
| f = test_values_8[j]; |
| num_failed += test_select_8(e, f); |
| num_all += 1; |
| } |
| } |
| |
| if (!num_failed) { |
| fprintf(stdout, "ok (ran %d tests)\n", num_all); |
| fprintf(stdout, "PASS\n"); |
| return EXIT_SUCCESS; |
| } else { |
| fprintf(stdout, "%d of %d tests failed!\n", num_failed, num_all); |
| return EXIT_FAILURE; |
| } |
| } |
