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#include "mult.h"
#include "point.h"
static void scalar_mult_inner(bn_t *scalar, point_t *point, curve_t *curve, point_t *out) {
point_t *a = point_copy(curve->neutral);
point_t *b = point_copy(curve->neutral);
int order_blen = bn_bit_length(&curve->n);
int d = (order_blen + {{ scalarmult.width }} - 1) / {{ scalarmult.width }};
point_t **points = malloc(sizeof(point_t *) * d);
point_t *current = point_copy(point);
for (int i = 0; i < d; i++) {
points[i] = point_copy(current);
if (i != d - 1) {
for (int j = 0; j < {{ scalarmult.width }}; j++) {
point_dbl(current, curve, current);
}
}
}
point_free(current);
small_base_t *bs = bn_convert_base_small(scalar, {{ 2**scalarmult.width }});
for (int j = {{ 2**scalarmult.width }}; j > 0; j--) {
{%- if scalarmult.direction == ProcessingDirection.RTL %}
for (int i = 0; i < bs->length; i++) {
if (bs->data[i] == j) {
point_accumulate(b, points[i], curve, b);
}
}
{%- else %}
for (int i = bs->length - 1; i >= 0; i--) {
if (bs->data[i] == j) {
point_accumulate(b, points[i], curve, b);
}
}
{%- endif -%}
{%- if scalarmult.short_circuit %}
if (point_equals(a, b)) {
point_dbl(b, curve, a);
continue;
}
{%- endif %}
point_accumulate(a, b, curve, a);
}
bn_small_base_clear(bs);
{%- if "scl" in scalarmult.formulas %}
point_scl(a, curve, a);
{%- endif %}
point_set(a, out);
for (long i = 0; i < d; i++) {
point_free(points[i]);
}
free(points);
point_free(a);
point_free(b);
}
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