/* a and b must be the same size, which is n2.
* r needs to be n2 words and t needs to be n2*2
*/
void bn_mul_low_recursive(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n2,
BN_ULONG *t)
{
int n=n2/2;
# ifdef BN_COUNT
fprintf(stderr," bn_mul_low_recursive %d * %d\n",n2,n2);
# endif
bn_mul_recursive(r,a,b,n,0,0,&(t[0]));
if (n >= BN_MUL_LOW_RECURSIVE_SIZE_NORMAL)
{
bn_mul_low_recursive(&(t[0]),&(a[0]),&(b[n]),n,&(t[n2]));
bn_add_words(&(r[n]),&(r[n]),&(t[0]),n);
bn_mul_low_recursive(&(t[0]),&(a[n]),&(b[0]),n,&(t[n2]));
bn_add_words(&(r[n]),&(r[n]),&(t[0]),n);
}
else
{
bn_mul_low_normal(&(t[0]),&(a[0]),&(b[n]),n);
bn_mul_low_normal(&(t[n]),&(a[n]),&(b[0]),n);
bn_add_words(&(r[n]),&(r[n]),&(t[0]),n);
bn_add_words(&(r[n]),&(r[n]),&(t[n]),n);
}
}
/*-
* a and b must be the same size, which is n2.
* r needs to be n2 words and t needs to be n2*2
*/
void bn_mul_low_recursive(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n2,
BN_ULONG *t)
{
int n = n2 / 2;
bn_mul_recursive(r, a, b, n, 0, 0, &(t[0]));
if (n >= BN_MUL_LOW_RECURSIVE_SIZE_NORMAL) {
bn_mul_low_recursive(&(t[0]), &(a[0]), &(b[n]), n, &(t[n2]));
bn_add_words(&(r[n]), &(r[n]), &(t[0]), n);
bn_mul_low_recursive(&(t[0]), &(a[n]), &(b[0]), n, &(t[n2]));
bn_add_words(&(r[n]), &(r[n]), &(t[0]), n);
} else {
bn_mul_low_normal(&(t[0]), &(a[0]), &(b[n]), n);
bn_mul_low_normal(&(t[n]), &(a[n]), &(b[0]), n);
bn_add_words(&(r[n]), &(r[n]), &(t[0]), n);
bn_add_words(&(r[n]), &(r[n]), &(t[n]), n);
}
}