tests/suites/test_suite_constant_time.function

/* 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 <mbedtls/constant_time.h>
#include <constant_time_internal.h>
#include <constant_time_invasive.h>

#include <test/constant_flow.h>
/* END_HEADER */

/* BEGIN_CASE depends_on:MBEDTLS_SSL_SOME_SUITES_USE_TLS_CBC:MBEDTLS_TEST_HOOKS */
void ssl_cf_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;

    ASSERT_ALLOC( dst, len );
    ASSERT_ALLOC( 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 ) );
        mbedtls_ct_memcpy_offset( dst, src, secret,
                                  offset_min, offset_max, len );
        TEST_CF_PUBLIC( &secret, sizeof( secret ) );
        TEST_CF_PUBLIC( dst, len );

        ASSERT_COMPARE( dst, len, src + secret, len );
    }

exit:
    mbedtls_free( dst );
    mbedtls_free( src );
}
/* END_CASE */