/*  test_hmac_prng.c - TinyCrypt implementation of some HMAC-PRNG tests */

/*
    Copyright (C) 2017 by Intel Corporation, All Rights Reserved.

    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions are met:

      - Redistributions of source code must retain the above copyright notice,
       this list of conditions and the following disclaimer.

      - 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.

      - Neither the name of Intel Corporation nor the names of its contributors
      may be used to endorse or promote products derived from this software
      without specific prior written permission.

    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 COPYRIGHT OWNER 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.
*/

/*
    DESCRIPTION
    This module tests the following PRNG routines:

    Scenarios tested include:
    - HMAC-PRNG init
    - HMAC-PRNG reseed
    - HMAC-PRNG generate)
*/

#include <tinycrypt/hmac_prng.h>
#include <tinycrypt/constants.h>
#include <test_utils.h>

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define TC_DEBUG_MODE 0

#ifdef TC_DEBUG_MODE
void show(const char* label, const uint8_t* s, size_t len)
{
    unsigned int i;
    printf ("%s = ", label);

    for (i = 0; i < (unsigned int) len; ++i)
    {
        printf ("%02x", s[i]);
    }

    printf ("\n");
}

void printBinaryFile(const uint8_t* s, unsigned int slen)
{
    FILE* write_ptr;
    write_ptr = fopen("pseudo-random-data.bin","wb");
    fwrite(s, slen, 1, write_ptr);
}
#endif

/*
    Main task to test AES
*/
int main(void)
{
    uint8_t seed[128];
    struct tc_hmac_prng_struct h;
    unsigned int size = (1 << 19);
    uint8_t random[size];
    unsigned int i;
    unsigned int result = TC_PASS;
    TC_START("Performing HMAC-PRNG tests:");
    TC_PRINT("HMAC-PRNG test#1 (init, reseed, generate):\n");

    /* Fake seed (replace by a a truly random seed): */
    for (i = 0; i < (unsigned int) sizeof(seed); ++i)
    {
        seed[i] = i;
    }

    /*  Fake personalization and additional_input (replace by appropriate
        values):
        e.g.: hostname+timestamp */
    uint8_t* personalization = (uint8_t*) "HOSTNAME";
    uint8_t* additional_input = (uint8_t*) "additional input";
    TC_PRINT("HMAC-PRNG test#1 (init):\n");

    if (tc_hmac_prng_init(&h, personalization,
                          sizeof(personalization)) == 0)
    {
        TC_ERROR("HMAC-PRNG initialization failed.\n");
        result = TC_FAIL;
        goto exitTest;
    }

    TC_END_RESULT(result);
    TC_PRINT("HMAC-PRNG test#1 (reseed):\n");

    if (tc_hmac_prng_reseed(&h, seed, sizeof(seed), additional_input,
                            sizeof(additional_input)) == 0)
    {
        TC_ERROR("HMAC-PRNG reseed failed.\n");
        result = TC_FAIL;
        goto exitTest;
    }

    TC_END_RESULT(result);
    TC_PRINT("HMAC-PRNG test#1 (generate):\n");

    if (tc_hmac_prng_generate(random, size, &h) < 1)
    {
        TC_ERROR("HMAC-PRNG generate failed.\n");
        result = TC_FAIL;
        goto exitTest;
    }

    TC_END_RESULT(result);
    #ifdef TC_DEBUG_MODE
    printBinaryFile(random, size);
    show ("Pseudo-random data", random, size);
    #endif
    TC_PRINT("All HMAC tests succeeded!\n");
exitTest:
    TC_END_RESULT(result);
    TC_END_REPORT(result);
}
