C++ (Cpp) fp_prime_calc примеры использования

Пример #1

Файл: relic_fp_prime.c Проект: ace0/relic

/**
 * Assigns the prime field modulus.
 *
 * @param[in] p			- the new prime field modulus.
 */
static void fp_prime_set(const bn_t p) {
	dv_t s, q;
	bn_t t;
	ctx_t *ctx = core_get();

	if (p->used != FP_DIGS) {
		THROW(ERR_NO_VALID);
	}

	dv_null(s);
	bn_null(t);
	dv_null(q);

	TRY {
		dv_new(s);
		bn_new(t);
		dv_new(q);

		bn_copy(&(ctx->prime), p);

		bn_mod_dig(&(ctx->mod8), &(ctx->prime), 8);

		switch (ctx->mod8) {
			case 3:
			case 7:
				ctx->qnr = -1;
				/* The current code for extensions of Fp^3 relies on qnr being
				 * also a cubic non-residue. */
				ctx->cnr = 0;
				break;
			case 1:
			case 5:
				ctx->qnr = ctx->cnr = -2;
				break;
			default:
				ctx->qnr = ctx->cnr = 0;
				THROW(ERR_NO_VALID);
				break;
		}
#ifdef FP_QNRES
		if (ctx->mod8 != 3) {
			THROW(ERR_NO_VALID);
		}
#endif

#if FP_RDC == MONTY || !defined(STRIP)
		bn_mod_pre_monty(t, &(ctx->prime));
		ctx->u = t->dp[0];
		dv_zero(s, 2 * FP_DIGS);
		s[2 * FP_DIGS] = 1;
		dv_zero(q, 2 * FP_DIGS + 1);
		dv_copy(q, ctx->prime.dp, FP_DIGS);
		bn_divn_low(t->dp, ctx->conv.dp, s, 2 * FP_DIGS + 1, q, FP_DIGS);
		ctx->conv.used = FP_DIGS;
		bn_trim(&(ctx->conv));
		bn_set_dig(&(ctx->one), 1);
		bn_lsh(&(ctx->one), &(ctx->one), ctx->prime.used * BN_DIGIT);
		bn_mod(&(ctx->one), &(ctx->one), &(ctx->prime));
#endif
		fp_prime_calc();
	}
	CATCH_ANY {
		THROW(ERR_CAUGHT);
	}
	FINALLY {
		bn_free(t);
		dv_free(s);
		dv_free(q);
	}
}

Пример #2

Файл: relic_ep2_curve.c Проект: enascimento/relic-git-avr

void ep2_curve_set_twist(int type) {
	char str[2 * FP_BYTES + 1];
	ctx_t *ctx = core_get();
	ep2_t g;
	fp2_t a;
	fp2_t b;
	bn_t r;

	ep2_null(g);
	fp2_null(a);
	fp2_null(b);
	bn_null(r);

	ctx->ep2_is_twist = 0;
	if (type == EP_MTYPE || type == EP_DTYPE) {
		ctx->ep2_is_twist = type;
	} else {
		return;
	}

	TRY {
		ep2_new(g);
		fp2_new(a);
		fp2_new(b);
		bn_new(r);

		switch (ep_param_get()) {
#if FP_PRIME == 158
			case BN_P158:
				ASSIGN(BN_P158);
				break;
#elif FP_PRIME == 254
			case BN_P254:
				ASSIGN(BN_P254);
				break;
#elif FP_PRIME == 256
			case BN_P256:
				ASSIGN(BN_P256);
				break;
#elif FP_PRIME == 638
			case BN_P638:
				ASSIGN(BN_P638);
				break;
			case B12_P638:
				ASSIGN(B12_P638);
				break;
#endif
			default:
				(void)str;
				THROW(ERR_NO_VALID);
				break;
		}

		fp2_zero(g->z);
		fp_set_dig(g->z[0], 1);
		g->norm = 1;

		ep2_copy(&(ctx->ep2_g), g);
		fp_copy(ctx->ep2_a[0], a[0]);
		fp_copy(ctx->ep2_a[1], a[1]);
		fp_copy(ctx->ep2_b[0], b[0]);
		fp_copy(ctx->ep2_b[1], b[1]);
		bn_copy(&(ctx->ep2_r), r);

		/* I don't have a better place for this. */
		fp_prime_calc();

#if defined(EP_PRECO)
		ep2_mul_pre((ep2_t *)ep2_curve_get_tab(), &(ctx->ep2_g));
#endif
	}
	CATCH_ANY {
		THROW(ERR_CAUGHT);
	}
	FINALLY {
		ep2_free(g);
		fp2_free(a);
		fp2_free(b);
		bn_free(r);
	}
}