/* Microsoft Reference Implementation for TPM 2.0
 *
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//** Introduction
//
// The functions in this file are used for initialization of the interface to the
// LibTomCrypt and MpsLib libraries. This is not used if only the LTC hash and
// symmetric functions are used.

//** Defines and Includes

#include "Tpm.h"

#if defined(HASH_LIB_LTC) || defined(MATH_LIB_LTC) || defined(SYM_LIB_LTC)

// This state is used because there is no way to pass the random number state
// to LibTomCrypt. I do not think that this is currently an issue because...
// Heck, just put in an assert and see what happens.
static void* s_randState;

//*** LtcRand()
// This is a stub function that is called from the LibTomCrypt or libmpa code
// to get a random number. In turn, this will call the random RandGenerate
// function that was passed in LibraryInit(). This function will pass the pointer
// to the current rand state along with the random byte request.
uint32_t LtcRand(void* buf, size_t blen)
{
    pAssert(1);
    DRBG_Generate(s_randState, buf, (uint16_t)blen);
    return 0;
}

//*** SupportLibInit()
// This does any initialization required by the support library.
LIB_EXPORT int SupportLibInit(void)
{
    mpa_set_random_generator(LtcRand);
    s_randState       = NULL;
    external_mem_pool = NULL;
    return 1;
}

//*** LtcPoolInit()
// Function to initialize a pool. ****
LIB_EXPORT mpa_scratch_mem LtcPoolInit(mpa_word_t* poolAddress, int vars, int bits)
{
    mpa_scratch_mem pool = (mpa_scratch_mem)poolAddress;
    mpa_init_scratch_mem(pool, vars, bits);
    init_mpa_tomcrypt(pool);
    return pool;
}

#endif  // HASH_LIB_LTC || MATH_LIB_LTC || SYM_LIB_LTC
