void eb_curve_set_ordin(fb_t a, fb_t b, eb_t g, bn_t r, bn_t h) {
fb_copy(curve_a, a);
fb_copy(curve_b, b);
detect_opt(&curve_opt_a, curve_a);
detect_opt(&curve_opt_b, curve_b);
curve_is_super = 0;
if (fb_cmp_dig(curve_b, 1) == CMP_EQ) {
curve_is_kbltz = 1;
} else {
curve_is_kbltz = 0;
}
#if defined(EB_KBLTZ) && (EB_MUL == LWNAF || EB_FIX == LWNAF || EB_SIM == INTER || !defined(STRIP))
if (curve_is_kbltz) {
compute_kbltz();
}
#endif
eb_norm(g, g);
eb_copy(&curve_g, g);
bn_copy(&curve_r, r);
bn_copy(&curve_h, h);
#if defined(EB_PRECO)
eb_mul_pre(eb_curve_get_tab(), &curve_g);
#endif
}
void eb_curve_set_ordin(const fb_t a, const fb_t b, const eb_t g, const bn_t r,
const bn_t h) {
ctx_t *ctx = core_get();
fb_copy(ctx->eb_a, a);
fb_copy(ctx->eb_b, b);
detect_opt(&(ctx->eb_opt_a), ctx->eb_a);
detect_opt(&(ctx->eb_opt_b), ctx->eb_b);
ctx->eb_is_super = 0;
if (fb_cmp_dig(ctx->eb_b, 1) == CMP_EQ) {
ctx->eb_is_kbltz = 1;
} else {
ctx->eb_is_kbltz = 0;
}
#if defined(EB_KBLTZ) && (EB_MUL == LWNAF || EB_FIX == LWNAF || EB_SIM == INTER || !defined(STRIP))
if (ctx->eb_is_kbltz) {
compute_kbltz();
}
#endif
eb_norm(&(ctx->eb_g), g);
bn_copy(&(ctx->eb_r), r);
bn_copy(&(ctx->eb_h), h);
#if defined(EB_PRECO)
eb_mul_pre((eb_t *)eb_curve_get_tab(), &(ctx->eb_g));
#endif
}
/**
* Detects an optimization based on the curve coefficients.
*
* @param opt - the resulting optimization.
* @param a - the curve coefficient.
*/
static void detect_opt(int *opt, fb_t a) {
if (fb_is_zero(a)) {
*opt = OPT_ZERO;
} else {
if (fb_cmp_dig(a, 1) == CMP_EQ) {
*opt = OPT_ONE;
} else {
if (fb_bits(a) <= FB_DIGIT) {
*opt = OPT_DIGIT;
} else {
*opt = OPT_NONE;
}
}
}
}
