tests/src/helpers.c

/*
 *  Copyright The Mbed TLS Contributors
 *  SPDX-License-Identifier: Apache-2.0
 *
 *  Licensed under the Apache License, Version 2.0 (the "License"); you may
 *  not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */

#include <test/helpers.h>
#include <test/macros.h>
#include <string.h>

/*----------------------------------------------------------------------------*/
/* Static global variables */

#if defined(MBEDTLS_PLATFORM_C)
static mbedtls_platform_context platform_ctx;
#endif

mbedtls_test_info_t mbedtls_test_info;

/*----------------------------------------------------------------------------*/
/* Helper Functions */

int mbedtls_test_platform_setup(void)
{
    int ret = 0;
#if defined(MBEDTLS_PLATFORM_C)
    ret = mbedtls_platform_setup(&platform_ctx);
#endif /* MBEDTLS_PLATFORM_C */
    return ret;
}

void mbedtls_test_platform_teardown(void)
{
#if defined(MBEDTLS_PLATFORM_C)
    mbedtls_platform_teardown(&platform_ctx);
#endif /* MBEDTLS_PLATFORM_C */
}

static int ascii2uc(const char c, unsigned char *uc)
{
    if ((c >= '0') && (c <= '9'))
        *uc = c - '0';
    else if ((c >= 'a') && (c <= 'f'))
        *uc = c - 'a' + 10;
    else if ((c >= 'A') && (c <= 'F'))
        *uc = c - 'A' + 10;
    else
        return -1;

    return 0;
}

void mbedtls_test_fail(const char *test, int line_no, const char *filename)
{
    if (mbedtls_test_info.result == MBEDTLS_TEST_RESULT_FAILED) {
        /* We've already recorded the test as having failed. Don't
         * overwrite any previous information about the failure. */
        return;
    }
    mbedtls_test_info.result = MBEDTLS_TEST_RESULT_FAILED;
    mbedtls_test_info.test = test;
    mbedtls_test_info.line_no = line_no;
    mbedtls_test_info.filename = filename;
}

void mbedtls_test_skip(const char *test, int line_no, const char *filename)
{
    mbedtls_test_info.result = MBEDTLS_TEST_RESULT_SKIPPED;
    mbedtls_test_info.test = test;
    mbedtls_test_info.line_no = line_no;
    mbedtls_test_info.filename = filename;
}

void mbedtls_test_set_step(unsigned long step)
{
    mbedtls_test_info.step = step;
}

void mbedtls_test_info_reset(void)
{
    mbedtls_test_info.result = MBEDTLS_TEST_RESULT_SUCCESS;
    mbedtls_test_info.step = (unsigned long)(-1);
    mbedtls_test_info.test = 0;
    mbedtls_test_info.line_no = 0;
    mbedtls_test_info.filename = 0;
}

int mbedtls_test_unhexify(unsigned char *obuf,
                          size_t obufmax,
                          const char *ibuf,
                          size_t *len)
{
    unsigned char uc, uc2;

    *len = strlen(ibuf);

    /* Must be even number of bytes. */
    if ((*len) & 1)
        return -1;
    *len /= 2;

    if ((*len) > obufmax)
        return -1;

    while (*ibuf != 0) {
        if (ascii2uc(*(ibuf++), &uc) != 0)
            return -1;

        if (ascii2uc(*(ibuf++), &uc2) != 0)
            return -1;

        *(obuf++) = (uc << 4) | uc2;
    }

    return 0;
}

void mbedtls_test_hexify(unsigned char *obuf,
                         const unsigned char *ibuf,
                         int len)
{
    unsigned char l, h;

    while (len != 0) {
        h = *ibuf / 16;
        l = *ibuf % 16;

        if (h < 10)
            *obuf++ = '0' + h;
        else
            *obuf++ = 'a' + h - 10;

        if (l < 10)
            *obuf++ = '0' + l;
        else
            *obuf++ = 'a' + l - 10;

        ++ibuf;
        len--;
    }
}

unsigned char *mbedtls_test_zero_alloc(size_t len)
{
    void *p;
    size_t actual_len = (len != 0) ? len : 1;

    p = mbedtls_calloc(1, actual_len);
    TEST_HELPER_ASSERT(p != NULL);

    memset(p, 0x00, actual_len);

    return p;
}

unsigned char *mbedtls_test_unhexify_alloc(const char *ibuf, size_t *olen)
{
    unsigned char *obuf;
    size_t len;

    *olen = strlen(ibuf) / 2;

    if (*olen == 0)
        return mbedtls_test_zero_alloc(*olen);

    obuf = mbedtls_calloc(1, *olen);
    TEST_HELPER_ASSERT(obuf != NULL);
    TEST_HELPER_ASSERT(mbedtls_test_unhexify(obuf, *olen, ibuf, &len) == 0);

    return obuf;
}

int mbedtls_test_hexcmp(uint8_t *a, uint8_t *b, uint32_t a_len, uint32_t b_len)
{
    int ret = 0;
    uint32_t i = 0;

    if (a_len != b_len)
        return -1;

    for (i = 0; i < a_len; i++) {
        if (a[i] != b[i]) {
            ret = -1;
            break;
        }
    }
    return ret;
}

#if defined(MBEDTLS_TEST_HOOKS)
void mbedtls_test_err_add_check(int high, int low, const char *file, int line)
{
    /* Error codes are always negative (a value of zero is a success) however
     * their positive opposites can be easier to understand. The following
     * examples given in comments have been made positive for ease of
     * understanding. The structure of an error code is such:
     *
     *                                                shhhhhhhhlllllll
     *
     * s = sign bit.
     * h = high level error code (includes high level module ID (bits 12..14)
     *     and module-dependent error code (bits 7..11)).
     * l = low level error code.
     */
    if (high > -0x1000 && high != 0)
    /* high < 0001000000000000
     * No high level module ID bits are set.
     */
    {
        mbedtls_test_fail("'high' is not a high-level error code", line, file);
    } else if (high < -0x7F80)
    /* high > 0111111110000000
     * Error code is greater than the largest allowed high level module ID.
     */
    {
        mbedtls_test_fail("'high' error code is greater than 15 bits", line,
                          file);
    } else if ((high & 0x7F) != 0)
    /* high & 0000000001111111
     * Error code contains low level error code bits.
     */
    {
        mbedtls_test_fail("'high' contains a low-level error code", line, file);
    } else if (low < -0x007F)
    /* low >  0000000001111111
     * Error code contains high or module level error code bits.
     */
    {
        mbedtls_test_fail("'low' error code is greater than 7 bits", line,
                          file);
    } else if (low > 0) {
        mbedtls_test_fail("'low' error code is greater than zero", line, file);
    }
}
#endif /* MBEDTLS_TEST_HOOKS */

#if defined(MBEDTLS_BIGNUM_C)
int mbedtls_test_read_mpi(mbedtls_mpi *X, int radix, const char *s)
{
    /* mbedtls_mpi_read_string() currently retains leading zeros.
     * It always allocates at least one limb for the value 0. */
    if (s[0] == 0) {
        mbedtls_mpi_free(X);
        return 0;
    } else
        return mbedtls_mpi_read_string(X, radix, s);
}
#endif