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#include <string.h>
#include "crypto_additions.h"
#include "sc.h"
/* l = order of base point = 2^252 + 27742317777372353535851937790883648493 */
/*
static unsigned char l[32] = {0xed, 0xd3, 0xf5, 0x5c, 0x1a, 0x63, 0x12, 0x58,
0xd6, 0x9c, 0xf7, 0xa2, 0xde, 0xf9, 0xde, 0x14,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0, 0x10};
*/
static unsigned char lminus1[32] = {0xec, 0xd3, 0xf5, 0x5c, 0x1a, 0x63, 0x12, 0x58,
0xd6, 0x9c, 0xf7, 0xa2, 0xde, 0xf9, 0xde, 0x14,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x10};
/* b = -a (mod l) */
void sc_neg(unsigned char *b, const unsigned char *a)
{
unsigned char zero[32];
memset(zero, 0, 32);
sc_muladd(b, lminus1, a, zero); /* b = (-1)a + 0 (mod l) */
}
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