Esempio n. 1
0
/*---------------------------------------------------------------------------*/
void
ecc_add(point_t * P0, point_t * P1, point_t * P2)
{
  NN_DIGIT Z0[NUMWORDS];
  NN_DIGIT Z1[NUMWORDS];
  NN_DIGIT Z2[NUMWORDS];

  p_clear(P0);
  NN_AssignZero(Z0, NUMWORDS);
  NN_AssignZero(Z1, NUMWORDS);
  NN_AssignZero(Z2, NUMWORDS);
  Z1[0] = 0x01;
  Z2[0] = 0x01;

#ifdef ADD_MIX
    c_add_mix(P0, Z0, P1, Z1, P2);
#else
    ecc_add_proj(P0, Z0, P1, Z1, P2, Z2);
#endif

  if(!Z_is_one(Z0)) {
    NN_ModInv(Z1, Z0, param.p, NUMWORDS);
    NN_ModMultOpt(Z0, Z1, Z1, param.p, param.omega, NUMWORDS);
    NN_ModMultOpt(P0->x, P0->x, Z0, param.p, param.omega, NUMWORDS);
    NN_ModMultOpt(Z0, Z0, Z1, param.p, param.omega, NUMWORDS);
    NN_ModMultOpt(P0->y, P0->y, Z0, param.p, param.omega, NUMWORDS);
  }

}
Esempio n. 2
0
/*
 * scalar point multiplication
 * P0 = n*basepoint
 * pointArray is array of basepoint, pointArray[0] = basepoint, pointArray[1] = 2*basepoint ...
 */
void
ecc_win_mul(point_t * P0, NN_DIGIT * n, point_t * pointArray)
{

  int16_t i, tmp;
  int8_t j;
  NN_DIGIT windex;
  NN_DIGIT Z0[NUMWORDS];
  NN_DIGIT Z1[NUMWORDS];
#ifndef REPEAT_DOUBLE
  int8_t k;
#endif

  p_clear(P0);

  /* Convert to Jprojective coordinate */
  NN_AssignZero(Z0, NUMWORDS);
  NN_AssignZero(Z1, NUMWORDS);
  Z1[0] = 0x01;

  tmp = NN_Digits(n, NUMWORDS);

  for(i = tmp - 1; i >= 0; i--) {
    for(j = NN_DIGIT_BITS/W_BITS - 1; j >= 0; j--) {

#ifndef REPEAT_DOUBLE
      for(k = 0; k < W_BITS; k++) {
        ecc_dbl_proj(P0, Z0, P0, Z0);
      }
#else
      ecc_m_dbl_projective(P0, Z0, W_BITS);
#endif

      windex = mask[j] & n[i];

      if(windex) {
        windex = windex >> (j*W_BITS);

#ifdef ADD_MIX
        c_add_mix(P0, Z0, P0, Z0, &(pointArray[windex-1]));
#else
	ecc_add_proj(P0, Z0, P0, Z0, &(pointArray[windex-1]), Z1);
#endif
      }
    }
  }


  /* Convert back to affine coordinate */
  if(!Z_is_one(Z0)) {
    NN_ModInv(Z1, Z0, param.p, NUMWORDS);
    NN_ModMultOpt(Z0, Z1, Z1, param.p, param.omega, NUMWORDS);
    NN_ModMultOpt(P0->x, P0->x, Z0, param.p, param.omega, NUMWORDS);
    NN_ModMultOpt(Z0, Z0, Z1, param.p, param.omega, NUMWORDS);
    NN_ModMultOpt(P0->y, P0->y, Z0, param.p, param.omega, NUMWORDS);
  }

}
Esempio n. 3
0
File: ecc.c Progetto: codeguru1/ecc
/*
 * P0 = n * P1
 */
void
ecc_mul ( point_t* P0, point_t* P1, NN_DIGIT* n )
{
	int16_t i, tmp;
	NN_DIGIT Z0[NUMWORDS];
	NN_DIGIT Z1[NUMWORDS];

	/* clear point */
	p_clear ( P0 );

	/* convert to Jprojective coordinate */
	NN_AssignZero ( Z0, NUMWORDS );
	NN_AssignZero ( Z1, NUMWORDS );
	Z1[0] = 0x01;

	tmp = NN_Bits ( n, NUMWORDS );

	for ( i = tmp-1; i >= 0; i-- )
	{
		ecc_dbl_proj ( P0, Z0, P0, Z0 );

		if ( b_testbit ( n, i ) )
		{

#ifdef ADD_MIX
			c_add_mix ( P0, Z0, P0, Z0, P1 );
#else
			ecc_add_proj ( P0, Z0, P0, Z0, P1, Z1 );
#endif
		}
	}

	/* convert back to affine coordinate */
	if ( !Z_is_one ( Z0 ) )
	{
		NN_ModInv ( Z1, Z0, param.p, NUMWORDS );
		NN_ModMultOpt ( Z0, Z1, Z1, param.p, param.omega, NUMWORDS );
		NN_ModMultOpt ( P0->x, P0->x, Z0, param.p, param.omega, NUMWORDS );
		NN_ModMultOpt ( Z0, Z0, Z1, param.p, param.omega, NUMWORDS );
		NN_ModMultOpt ( P0->y, P0->y, Z0, param.p, param.omega, NUMWORDS );
	}

}