#ifndef __LIBGSMKBIGNUM_POWM_H__
#define __LIBGSMKBIGNUM_POWM_H__

#include <stdint.h>
#include <stdlib.h>

#ifdef __cplusplus
extern "C" {
#endif

#ifdef USE32BITLIMB
typedef uint32_t limb_t;
typedef uint64_t dlimb_t;
#else
typedef uint64_t limb_t;
typedef unsigned int uint128_t __attribute__((mode(TI)));
typedef uint128_t dlimb_t;
#endif


/* import from serialized format, big endian byte representation
   return amount of limbs */
uint32_t mp_import( limb_t *dest, uint8_t const * src, uint32_t byte_size );
void mp_export( uint8_t *dest, const limb_t *scr, uint32_t limb_size );

/* This function works with precalculated parameters passed in r_square
   and r_inverse. The latter being 1, if the bottom limb_t is -1. */
void powm_internal( limb_t * result,
              const limb_t * base,     uint32_t base_limbs,
              const limb_t * exponent, uint32_t exp_limbs,
              const limb_t * modulus,  uint32_t mod_limbs,
              const limb_t * r_square, const limb_t r_inverse );

/* Not yet implemented */
void powm( limb_t * result,
     const limb_t * base,     uint32_t base_limbs,
     const limb_t * exponent, int expbits,
     const limb_t * modulus,  uint32_t mod_limbs );

#ifdef __cplusplus
}
#endif

#endif