bn_mul_normal
void bn_mul_normal(BN_ULONG *r, BN_ULONG *a, int na, BN_ULONG *b, int nb);
bn_mul_normal(rr->d, a->d, al, b->d, bl);
bn_mul_normal(r, a, n2 + dna, b, n2 + dnb);
bn_mul_normal(r, a, n + tna, b, n + tnb);
bn_mul_normal(&(r[n2]), &(a[n]), tn, &(b[n]), tn);
bn_mul_normal(&(r[n2]), &(a[n]), tna, &(b[n]), tnb);
bn_mul_normal(&(r[n2]), &(a[n]), tna,