| /* BEGIN_HEADER */ |
| /** \file test_suite_constant_time.function |
| * |
| * Functional testing of functions in the constant_time module. |
| * |
| * The tests are instrumented with #TEST_CF_SECRET and #TEST_CF_PUBLIC |
| * (see tests/include/test/constant_flow.h) so that running the tests |
| * under MSan or Valgrind will detect a non-constant-time implementation. |
| */ |
| |
| #include <stdio.h> |
| |
| #include <limits.h> |
| #include <stdlib.h> |
| #include <errno.h> |
| |
| #include <mbedtls/bignum.h> |
| #include <mbedtls/constant_time.h> |
| #include <constant_time_internal.h> |
| |
| #include <test/constant_flow.h> |
| /* END_HEADER */ |
| |
| /* BEGIN_CASE */ |
| void mbedtls_ct_memcmp_null() |
| { |
| uint32_t x = 0; |
| TEST_ASSERT(mbedtls_ct_memcmp(&x, NULL, 0) == 0); |
| TEST_ASSERT(mbedtls_ct_memcmp(NULL, &x, 0) == 0); |
| TEST_ASSERT(mbedtls_ct_memcmp(NULL, NULL, 0) == 0); |
| } |
| /* END_CASE */ |
| |
| /* BEGIN_CASE */ |
| void mbedtls_ct_bool(char *input) |
| { |
| mbedtls_ct_uint_t v = (mbedtls_ct_uint_t) strtoull(input, NULL, 16); |
| TEST_ASSERT(errno == 0); |
| |
| mbedtls_ct_condition_t expected = (v != 0) ? MBEDTLS_CT_TRUE : MBEDTLS_CT_FALSE; |
| TEST_CF_SECRET(&v, sizeof(v)); |
| TEST_EQUAL(mbedtls_ct_bool(v), expected); |
| TEST_CF_PUBLIC(&v, sizeof(v)); |
| } |
| /* END_CASE */ |
| |
| /* BEGIN_CASE */ |
| void mbedtls_ct_bool_xxx(char *x_str, char *y_str) |
| { |
| mbedtls_ct_uint_t x = strtoull(x_str, NULL, 0); |
| mbedtls_ct_uint_t y = strtoull(y_str, NULL, 0); |
| |
| mbedtls_ct_uint_t x1 = x; |
| mbedtls_ct_uint_t y1 = y; |
| |
| TEST_CF_SECRET(&x, sizeof(x)); |
| TEST_CF_SECRET(&y, sizeof(y)); |
| |
| mbedtls_ct_condition_t expected = x1 ? MBEDTLS_CT_FALSE : MBEDTLS_CT_TRUE; |
| TEST_EQUAL(mbedtls_ct_bool_not(mbedtls_ct_bool(x)), expected); |
| |
| expected = x1 != y1 ? MBEDTLS_CT_TRUE : MBEDTLS_CT_FALSE; |
| TEST_EQUAL(mbedtls_ct_uint_ne(x, y), expected); |
| |
| expected = x1 == y1 ? MBEDTLS_CT_TRUE : MBEDTLS_CT_FALSE; |
| TEST_EQUAL(mbedtls_ct_uint_eq(x, y), expected); |
| |
| expected = x1 > y1 ? MBEDTLS_CT_TRUE : MBEDTLS_CT_FALSE; |
| TEST_EQUAL(mbedtls_ct_uint_gt(x, y), expected); |
| |
| expected = x1 < y1 ? MBEDTLS_CT_TRUE : MBEDTLS_CT_FALSE; |
| TEST_EQUAL(mbedtls_ct_uint_lt(x, y), expected); |
| |
| expected = x1 >= y1 ? MBEDTLS_CT_TRUE : MBEDTLS_CT_FALSE; |
| TEST_EQUAL(mbedtls_ct_uint_ge(x, y), expected); |
| |
| expected = x1 <= y1 ? MBEDTLS_CT_TRUE : MBEDTLS_CT_FALSE; |
| TEST_EQUAL(mbedtls_ct_uint_le(x, y), expected); |
| |
| expected = (!!x1) != (!!y1) ? MBEDTLS_CT_TRUE : MBEDTLS_CT_FALSE; |
| TEST_EQUAL(mbedtls_ct_bool_ne(mbedtls_ct_bool(x), mbedtls_ct_bool(y)), expected); |
| |
| expected = (!!x1) && (!!y1) ? MBEDTLS_CT_TRUE : MBEDTLS_CT_FALSE; |
| TEST_EQUAL(mbedtls_ct_bool_and(mbedtls_ct_bool(x), mbedtls_ct_bool(y)), expected); |
| |
| expected = (!!x1) || (!!y1) ? MBEDTLS_CT_TRUE : MBEDTLS_CT_FALSE; |
| TEST_EQUAL(mbedtls_ct_bool_or(mbedtls_ct_bool(x), mbedtls_ct_bool(y)), expected); |
| |
| TEST_CF_PUBLIC(&x, sizeof(x)); |
| TEST_CF_PUBLIC(&y, sizeof(y)); |
| } |
| /* END_CASE */ |
| |
| /* BEGIN_CASE depends_on:MBEDTLS_BASE64_C */ |
| void mbedtls_ct_uchar_in_range_if(int li, int hi, int ti) |
| { |
| unsigned char l = li, h = hi, t = ti; |
| |
| for (unsigned x = 0; x <= 255; x++) { |
| unsigned char expected = (x >= l) && (x <= h) ? t : 0; |
| |
| TEST_CF_SECRET(&x, sizeof(x)); |
| TEST_CF_SECRET(&l, sizeof(l)); |
| TEST_CF_SECRET(&h, sizeof(h)); |
| TEST_CF_SECRET(&t, sizeof(t)); |
| |
| TEST_EQUAL(mbedtls_ct_uchar_in_range_if(l, h, (unsigned char) x, t), expected); |
| |
| TEST_CF_PUBLIC(&x, sizeof(x)); |
| TEST_CF_PUBLIC(&l, sizeof(l)); |
| TEST_CF_PUBLIC(&h, sizeof(h)); |
| TEST_CF_PUBLIC(&t, sizeof(t)); |
| } |
| } |
| /* END_CASE */ |
| |
| /* BEGIN_CASE */ |
| void mbedtls_ct_error_if(int cond, int t, int f) |
| { |
| mbedtls_ct_condition_t c = mbedtls_ct_bool(cond); |
| |
| int expected = c ? t : f; |
| int expected0 = c ? t : 0; |
| |
| TEST_CF_SECRET(&c, sizeof(c)); |
| TEST_CF_SECRET(&t, sizeof(t)); |
| TEST_CF_SECRET(&f, sizeof(f)); |
| |
| TEST_EQUAL(mbedtls_ct_error_if(c, t, f), expected); |
| TEST_EQUAL(mbedtls_ct_error_if_else_0(c, t), expected0); |
| |
| TEST_CF_PUBLIC(&c, sizeof(c)); |
| TEST_CF_PUBLIC(&t, sizeof(t)); |
| TEST_CF_PUBLIC(&f, sizeof(f)); |
| } |
| /* END_CASE */ |
| |
| /* BEGIN_CASE */ |
| void mbedtls_ct_if(char *c_str, char *t_str, char *f_str) |
| { |
| mbedtls_ct_condition_t c = mbedtls_ct_bool(strtoull(c_str, NULL, 16)); |
| mbedtls_ct_uint_t t = (mbedtls_ct_uint_t) strtoull(t_str, NULL, 16); |
| mbedtls_ct_uint_t f = (mbedtls_ct_uint_t) strtoull(f_str, NULL, 16); |
| |
| mbedtls_ct_uint_t expected = c ? t : f; |
| mbedtls_ct_uint_t expected0 = c ? t : 0; |
| |
| TEST_CF_SECRET(&c, sizeof(c)); |
| TEST_CF_SECRET(&t, sizeof(t)); |
| TEST_CF_SECRET(&f, sizeof(f)); |
| |
| TEST_EQUAL(mbedtls_ct_if(c, t, f), expected); |
| TEST_EQUAL(mbedtls_ct_size_if(c, t, f), (size_t) expected); |
| TEST_EQUAL(mbedtls_ct_uint_if(c, t, f), (unsigned) expected); |
| TEST_EQUAL(mbedtls_ct_bool_if(c, mbedtls_ct_bool(t), mbedtls_ct_bool(f)), |
| mbedtls_ct_bool(expected)); |
| #if defined(MBEDTLS_BIGNUM_C) |
| TEST_EQUAL(mbedtls_ct_mpi_uint_if(c, t, f), (mbedtls_mpi_uint) expected); |
| #endif |
| |
| TEST_EQUAL(mbedtls_ct_uint_if_else_0(c, t), (unsigned) expected0); |
| TEST_EQUAL(mbedtls_ct_size_if_else_0(c, (size_t) t), (size_t) expected0); |
| TEST_EQUAL(mbedtls_ct_bool_if_else_0(c, mbedtls_ct_bool(t)), mbedtls_ct_bool(expected0)); |
| #if defined(MBEDTLS_BIGNUM_C) |
| TEST_EQUAL(mbedtls_ct_mpi_uint_if_else_0(c, t), (mbedtls_mpi_uint) expected0); |
| #endif |
| |
| TEST_CF_PUBLIC(&c, sizeof(c)); |
| TEST_CF_PUBLIC(&t, sizeof(t)); |
| TEST_CF_PUBLIC(&f, sizeof(f)); |
| } |
| /* END_CASE */ |
| |
| /* BEGIN_CASE depends_on:MBEDTLS_PKCS1_V15:MBEDTLS_RSA_C:!MBEDTLS_RSA_ALT */ |
| void mbedtls_ct_zeroize_if(char *c_str, int len) |
| { |
| uint8_t *buf = NULL; |
| mbedtls_ct_condition_t c = mbedtls_ct_bool(strtoull(c_str, NULL, 16)); |
| |
| TEST_CALLOC(buf, len); |
| for (size_t i = 0; i < (size_t) len; i++) { |
| buf[i] = 1; |
| } |
| |
| TEST_CF_SECRET(&c, sizeof(c)); |
| TEST_CF_SECRET(buf, len); |
| mbedtls_ct_zeroize_if(c, buf, len); |
| TEST_CF_PUBLIC(&c, sizeof(c)); |
| TEST_CF_PUBLIC(buf, len); |
| |
| for (size_t i = 0; i < (size_t) len; i++) { |
| TEST_EQUAL(buf[i], c != 0 ? 0 : 1); |
| } |
| exit: |
| mbedtls_free(buf); |
| } |
| /* END_CASE */ |
| |
| /* BEGIN_CASE */ |
| void mbedtls_ct_memcmp_single_bit_diff() |
| { |
| uint8_t *a = NULL, *b = NULL; |
| size_t size = 32; |
| TEST_CALLOC(a, size); |
| TEST_CALLOC(b, size); |
| |
| TEST_CF_SECRET(a, size); |
| TEST_CF_SECRET(b, size); |
| int result = mbedtls_ct_memcmp(a, b, size); |
| TEST_CF_PUBLIC(a, size); |
| TEST_CF_PUBLIC(b, size); |
| TEST_CF_PUBLIC(&result, sizeof(result)); |
| |
| TEST_EQUAL(result, 0); |
| |
| for (size_t offset = 0; offset < size; offset++) { |
| for (size_t bit_offset = 0; bit_offset < 8; bit_offset++) { |
| /* Set a single bit to be different at given offset, to test that we |
| detect single-bit differences */ |
| a[offset] = 1 << bit_offset; |
| |
| TEST_CF_SECRET(a, size); |
| TEST_CF_SECRET(b, size); |
| result = mbedtls_ct_memcmp(a, b, size); |
| TEST_CF_PUBLIC(a, size); |
| TEST_CF_PUBLIC(b, size); |
| TEST_CF_PUBLIC(&result, sizeof(result)); |
| |
| TEST_ASSERT(result != 0); |
| |
| a[offset] = 0; |
| } |
| } |
| |
| |
| exit: |
| mbedtls_free(a); |
| mbedtls_free(b); |
| } |
| /* END_CASE */ |
| |
| /* BEGIN_CASE */ |
| void mbedtls_ct_memcmp(int same, int size, int offset) |
| { |
| uint8_t *a = NULL, *b = NULL; |
| TEST_CALLOC(a, size + offset); |
| TEST_CALLOC(b, size + offset); |
| |
| /* Construct data that matches, if same == -1, otherwise |
| * same gives the number of bytes (after the initial offset) |
| * that will match; after that it will differ. |
| */ |
| for (int i = 0; i < size + offset; i++) { |
| a[i] = i & 0xff; |
| if (same == -1 || (i - offset) < same) { |
| b[i] = a[i]; |
| } else { |
| b[i] = (i + 1) & 0xff; |
| } |
| } |
| |
| int reference = memcmp(a + offset, b + offset, size); |
| |
| TEST_CF_SECRET(a, size + offset); |
| TEST_CF_SECRET(b, size + offset); |
| |
| int actual = mbedtls_ct_memcmp(a + offset, b + offset, size); |
| |
| TEST_CF_PUBLIC(a, size + offset); |
| TEST_CF_PUBLIC(b, size + offset); |
| TEST_CF_PUBLIC(&actual, sizeof(actual)); |
| |
| if (same == -1 || same >= size) { |
| TEST_ASSERT(reference == 0); |
| TEST_ASSERT(actual == 0); |
| } else { |
| TEST_ASSERT(reference != 0); |
| TEST_ASSERT(actual != 0); |
| } |
| exit: |
| mbedtls_free(a); |
| mbedtls_free(b); |
| } |
| /* END_CASE */ |
| |
| /* BEGIN_CASE depends_on:MBEDTLS_NIST_KW_C */ |
| |
| /** |
| * Generate two arrays of the given size, and test mbedtls_ct_memcmp_partial |
| * over them. The arrays will be identical, except that one byte may be specified |
| * to be different. |
| * |
| * \p diff Index of byte that differs (if out of range, the arrays will match). |
| * \p size Size of arrays to compare |
| * \p skip_head Leading bytes to skip, as per mbedtls_ct_memcmp_partial |
| * \p skip_tail Trailing bytes to skip, as per mbedtls_ct_memcmp_partial |
| */ |
| void mbedtls_ct_memcmp_partial(int diff, int size, int skip_head, int skip_tail) |
| { |
| uint8_t *a = NULL, *b = NULL; |
| |
| TEST_CALLOC_NONNULL(a, size); |
| TEST_CALLOC_NONNULL(b, size); |
| |
| TEST_ASSERT((skip_head + skip_tail) <= size); |
| |
| /* Construct data that matches, except for specified byte (if in range). */ |
| for (int i = 0; i < size; i++) { |
| a[i] = i & 0xff; |
| b[i] = a[i]; |
| if (i == diff) { |
| // modify the specified byte |
| b[i] ^= 1; |
| } |
| } |
| |
| int reference = memcmp(a + skip_head, b + skip_head, size - skip_head - skip_tail); |
| |
| TEST_CF_SECRET(a, size); |
| TEST_CF_SECRET(b, size); |
| |
| int actual = mbedtls_ct_memcmp_partial(a, b, size, skip_head, skip_tail); |
| |
| TEST_CF_PUBLIC(a, size); |
| TEST_CF_PUBLIC(b, size); |
| TEST_CF_PUBLIC(&actual, sizeof(actual)); |
| |
| TEST_EQUAL(!!reference, !!actual); |
| exit: |
| mbedtls_free(a); |
| mbedtls_free(b); |
| } |
| /* END_CASE */ |
| |
| /* BEGIN_CASE */ |
| void mbedtls_ct_memcpy_if(int eq, int size, int offset) |
| { |
| uint8_t *src = NULL, *src2 = NULL, *result = NULL, *expected = NULL; |
| TEST_CALLOC(src, size + offset); |
| TEST_CALLOC(src2, size + offset); |
| TEST_CALLOC(result, size + offset); |
| TEST_CALLOC(expected, size + offset); |
| |
| /* Apply offset to result only */ |
| for (int i = 0; i < size + offset; i++) { |
| src[i] = 1; |
| result[i] = 0xff; |
| expected[i] = eq ? 1 : 0xff; |
| } |
| |
| int secret_eq = eq; |
| TEST_CF_SECRET(&secret_eq, sizeof(secret_eq)); |
| TEST_CF_SECRET(src, size + offset); |
| TEST_CF_SECRET(result, size + offset); |
| |
| mbedtls_ct_memcpy_if(mbedtls_ct_bool(secret_eq), result + offset, src, NULL, size); |
| |
| TEST_CF_PUBLIC(&secret_eq, sizeof(secret_eq)); |
| TEST_CF_PUBLIC(src, size + offset); |
| TEST_CF_PUBLIC(result, size + offset); |
| |
| TEST_MEMORY_COMPARE(expected, size, result + offset, size); |
| |
| |
| /* Apply offset to src only */ |
| for (int i = 0; i < size + offset; i++) { |
| src[i] = 1; |
| result[i] = 0xff; |
| expected[i] = eq ? 1 : 0xff; |
| } |
| |
| TEST_CF_SECRET(&secret_eq, sizeof(secret_eq)); |
| TEST_CF_SECRET(src, size + offset); |
| TEST_CF_SECRET(result, size + offset); |
| |
| mbedtls_ct_memcpy_if(mbedtls_ct_bool(secret_eq), result, src + offset, NULL, size); |
| |
| TEST_CF_PUBLIC(&secret_eq, sizeof(secret_eq)); |
| TEST_CF_PUBLIC(src, size + offset); |
| TEST_CF_PUBLIC(result, size + offset); |
| |
| TEST_MEMORY_COMPARE(expected, size, result, size); |
| |
| |
| /* Apply offset to src and src2 */ |
| for (int i = 0; i < size + offset; i++) { |
| src[i] = 1; |
| src2[i] = 2; |
| result[i] = 0xff; |
| expected[i] = eq ? 1 : 2; |
| } |
| |
| TEST_CF_SECRET(&secret_eq, sizeof(secret_eq)); |
| TEST_CF_SECRET(src, size + offset); |
| TEST_CF_SECRET(src2, size + offset); |
| TEST_CF_SECRET(result, size + offset); |
| |
| mbedtls_ct_memcpy_if(mbedtls_ct_bool(secret_eq), result, src + offset, src2 + offset, size); |
| |
| TEST_CF_PUBLIC(&secret_eq, sizeof(secret_eq)); |
| TEST_CF_PUBLIC(src, size + offset); |
| TEST_CF_SECRET(src2, size + offset); |
| TEST_CF_PUBLIC(result, size + offset); |
| |
| TEST_MEMORY_COMPARE(expected, size, result, size); |
| |
| |
| /* result == src == dest */ |
| for (int i = 0; i < size + offset; i++) { |
| src[i] = 2; |
| expected[i] = 2; |
| } |
| |
| TEST_CF_SECRET(&secret_eq, sizeof(secret_eq)); |
| TEST_CF_SECRET(src, size + offset); |
| TEST_CF_SECRET(result, size + offset); |
| |
| mbedtls_ct_memcpy_if(mbedtls_ct_bool(secret_eq), src + offset, src + offset, src + offset, |
| size); |
| |
| TEST_CF_PUBLIC(&secret_eq, sizeof(secret_eq)); |
| TEST_CF_PUBLIC(src, size + offset); |
| TEST_CF_PUBLIC(result, size + offset); |
| |
| TEST_MEMORY_COMPARE(expected, size, src + offset, size); |
| exit: |
| mbedtls_free(src); |
| mbedtls_free(src2); |
| mbedtls_free(result); |
| mbedtls_free(expected); |
| } |
| /* END_CASE */ |
| |
| /* BEGIN_CASE depends_on:MBEDTLS_PKCS1_V15:MBEDTLS_RSA_C:!MBEDTLS_RSA_ALT */ |
| void mbedtls_ct_memmove_left(int len, int offset) |
| { |
| size_t l = (size_t) len; |
| size_t o = (size_t) offset; |
| |
| uint8_t *buf = NULL, *buf_expected = NULL; |
| TEST_CALLOC(buf, l); |
| TEST_CALLOC(buf_expected, l); |
| |
| for (size_t i = 0; i < l; i++) { |
| buf[i] = (uint8_t) i; |
| buf_expected[i] = buf[i]; |
| } |
| |
| TEST_CF_SECRET(&o, sizeof(o)); |
| TEST_CF_SECRET(buf, l); |
| mbedtls_ct_memmove_left(buf, l, o); |
| TEST_CF_PUBLIC(&o, sizeof(o)); |
| TEST_CF_PUBLIC(buf, l); |
| |
| if (l > 0) { |
| memmove(buf_expected, buf_expected + o, l - o); |
| memset(buf_expected + (l - o), 0, o); |
| TEST_ASSERT(memcmp(buf, buf_expected, l) == 0); |
| } |
| exit: |
| mbedtls_free(buf); |
| mbedtls_free(buf_expected); |
| } |
| /* END_CASE */ |
| |
| /* BEGIN_CASE */ |
| void mbedtls_ct_memcpy_offset(int offset_min, int offset_max, int len) |
| { |
| unsigned char *dst = NULL; |
| unsigned char *src = NULL; |
| size_t src_len = offset_max + len; |
| size_t secret; |
| |
| TEST_CALLOC(dst, len); |
| TEST_CALLOC(src, src_len); |
| |
| /* Fill src in a way that we can detect if we copied the right bytes */ |
| mbedtls_test_rnd_std_rand(NULL, src, src_len); |
| |
| for (secret = offset_min; secret <= (size_t) offset_max; secret++) { |
| mbedtls_test_set_step((int) secret); |
| |
| TEST_CF_SECRET(&secret, sizeof(secret)); |
| TEST_CF_SECRET(src, len); |
| TEST_CF_SECRET(dst, len); |
| mbedtls_ct_memcpy_offset(dst, src, secret, |
| offset_min, offset_max, len); |
| TEST_CF_PUBLIC(&secret, sizeof(secret)); |
| TEST_CF_PUBLIC(src, len); |
| TEST_CF_PUBLIC(dst, len); |
| |
| TEST_MEMORY_COMPARE(dst, len, src + secret, len); |
| } |
| |
| exit: |
| mbedtls_free(dst); |
| mbedtls_free(src); |
| } |
| /* END_CASE */ |