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#include "mult.h"
#include "point.h"
void scalar_mult_ltr(int order_blen, point_t **points, bn_t *scalar, point_t *point, curve_t *curve) {
{%- if scalarmult.complete %}
int nbits = order_blen - 1;
{%- else %}
int nbits = bn_bit_length(scalar) - 1;
{%- endif %}
{%- if scalarmult.always %}
point_t *dummy = point_new();
{%- endif %}
for (int i = nbits; i >= 0; i--) {
if (bn_get_bit(scalar, i) == 1) {
point_accumulate(point, points[i], curve, point);
} else {
{%- if scalarmult.always %}
point_accumulate(point, points[i], curve, dummy);
{%- endif %}
}
}
{%- if scalarmult.always %}
point_free(dummy);
{%- endif %}
}
void scalar_mult_rtl(int order_blen, point_t **points, bn_t *scalar, point_t *point, curve_t *curve) {
{%- if scalarmult.complete %}
int nbits = order_blen;
{%- else %}
int nbits = bn_bit_length(scalar);
{%- endif %}
{%- if scalarmult.always %}
point_t *dummy = point_new();
{%- endif %}
for (int i = 0; i < nbits; i++) {
if (bn_get_bit(scalar, i) == 1) {
point_accumulate(point, points[i], curve, point);
} else {
{%- if scalarmult.always %}
point_accumulate(point, points[i], curve, dummy);
{%- endif %}
}
}
{%- if scalarmult.always %}
point_free(dummy);
{%- endif %}
}
static void scalar_mult_inner(bn_t *scalar, point_t *point, curve_t *curve, point_t *out) {
point_t *q = point_copy(curve->neutral);
int order_blen = bn_bit_length(&curve->n);
point_t **points = malloc(sizeof(point_t *) * (order_blen + 1));
point_t *current = point_copy(point);
for (int i = 0; i < order_blen + 1; i++) {
points[i] = point_copy(current);
if (i != order_blen) {
point_dbl(current, curve, current);
}
}
point_free(current);
{%- if scalarmult.direction == ProcessingDirection.LTR %}
scalar_mult_ltr(order_blen, points, scalar, q, curve);
{%- else %}
scalar_mult_rtl(order_blen, points, scalar, q, curve);
{%- endif %}
{%- if "scl" in scalarmult.formulas %}
point_scl(q, curve, q);
{%- endif %}
point_set(q, out);
for (int i = 0; i < order_blen + 1; i++) {
point_free(points[i]);
}
free(points);
point_free(q);
}
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