/* -*-c-*-
*
- * $Id: mpbarrett.c,v 1.2 1999/12/11 01:50:56 mdw Exp $
+ * $Id: mpbarrett.c,v 1.4 2000/06/17 11:45:09 mdw Exp $
*
* Barrett modular reduction
*
/*----- Revision history --------------------------------------------------*
*
* $Log: mpbarrett.c,v $
+ * Revision 1.4 2000/06/17 11:45:09 mdw
+ * Major memory management overhaul. Added arena support. Use the secure
+ * arena for secret integers. Replace and improve the MP management macros
+ * (e.g., replace MP_MODIFY by MP_DEST).
+ *
+ * Revision 1.3 1999/12/12 15:08:52 mdw
+ * Don't bother shifting %$q$% in @mpbarrett_reduce@, just skip the least
+ * significant digits.
+ *
* Revision 1.2 1999/12/11 01:50:56 mdw
* Improve initialization slightly.
*
mp_shrink(m);
mb->k = MP_LEN(m);
mb->m = MP_COPY(m);
- b = mp_create(2 * mb->k + 1);
+ b = mp_new(2 * mb->k + 1, 0);
MPX_ZERO(b->v, b->vl - 1);
b->vl[-1] = 1;
mp_div(&b, 0, b, m);
if (MP_LEN(m) < k) {
m = MP_COPY(m);
- MP_DROP(d);
+ if (d)
+ MP_DROP(d);
return (m);
}
mp qq;
mp_build(&qq, m->v + (k - 1), m->vl);
q = mp_mul(MP_NEW, &qq, mb->mu);
- q = mp_lsr(q, q, MPW_BITS * (k + 1));
+ if (MP_LEN(q) <= k) {
+ m = MP_COPY(m);
+ if (d)
+ MP_DROP(d);
+ return (m);
+ }
}
/* --- Second stage --- */
mvl = m->vl;
else
mvl = m->v + k + 1;
- r = mp_create(k + 1);
- mpx_umul(r->v, r->vl, q->v, q->vl, mb->m->v, mb->m->vl);
- r->f = (q->f | mb->m->f) & MP_BURN;
- MP_MODIFY(d, k + 1);
+ r = mp_new(k + 1, (q->f | mb->m->f) & MP_BURN);
+ mpx_umul(r->v, r->vl, q->v + k + 1, q->vl, mb->m->v, mb->m->vl);
+ MP_DEST(d, k + 1, r->f);
mpx_usub(d->v, d->vl, m->v, mvl, r->v, r->vl);
d->f = (m->f | r->f) & MP_BURN;
MP_DROP(r);
a = MP_COPY(a);
mp_scan(&sc, e);
+ if (e->f & MP_BURN)
+ spare = MP_NEWSEC;
if (MP_STEP(&sc)) {
size_t sq = 0;
for (;;) {