* [including the GNU Public Licence.]
*/
-#include <stdio.h>
#include "cryptlib.h"
#include "bn_lcl.h"
int ret = 0;
BIGNUM *tmp,*rr;
-#ifdef BN_COUNT
- fprintf(stderr,"BN_sqr %d * %d\n",a->top,a->top);
-#endif
bn_check_top(a);
al=a->top;
if (al <= 0)
{
r->top=0;
- return(1);
+ r->neg = 0;
+ return 1;
}
BN_CTX_start(ctx);
rr=(a != r) ? r : BN_CTX_get(ctx);
tmp=BN_CTX_get(ctx);
- if (tmp == NULL) goto err;
+ if (!rr || !tmp) goto err;
- max=(al+al);
- if (bn_wexpand(rr,max+1) == NULL) goto err;
+ max = 2 * al; /* Non-zero (from above) */
+ if (bn_wexpand(rr,max) == NULL) goto err;
if (al == 4)
{
#endif
}
- rr->top=max;
rr->neg=0;
- if ((max > 0) && (rr->d[max-1] == 0)) rr->top--;
+ /* If the most-significant half of the top word of 'a' is zero, then
+ * the square of 'a' will max-1 words. */
+ if(a->d[al - 1] == (a->d[al - 1] & BN_MASK2l))
+ rr->top = max - 1;
+ else
+ rr->top = max;
if (rr != r) BN_copy(r,rr);
ret = 1;
err:
+ bn_check_top(rr);
+ bn_check_top(tmp);
BN_CTX_end(ctx);
return(ret);
}
}
#ifdef BN_RECURSION
-/* r is 2*n words in size,
+/*-
+ * r is 2*n words in size,
* a and b are both n words in size. (There's not actually a 'b' here ...)
* n must be a power of 2.
* We multiply and return the result.
int zero,c1;
BN_ULONG ln,lo,*p;
-#ifdef BN_COUNT
- fprintf(stderr," bn_sqr_recursive %d * %d\n",n2,n2);
-#endif
if (n2 == 4)
{
#ifndef BN_SQR_COMBA
bn_sqr_recursive(r,a,n,p);
bn_sqr_recursive(&(r[n2]),&(a[n]),n,p);
- /* t[32] holds (a[0]-a[1])*(a[1]-a[0]), it is negative or zero
+ /*-
+ * t[32] holds (a[0]-a[1])*(a[1]-a[0]), it is negative or zero
* r[10] holds (a[0]*b[0])
* r[32] holds (b[1]*b[1])
*/
/* t[32] is negative */
c1-=(int)(bn_sub_words(&(t[n2]),t,&(t[n2]),n2));
- /* t[32] holds (a[0]-a[1])*(a[1]-a[0])+(a[0]*a[0])+(a[1]*a[1])
+ /*-
+ * t[32] holds (a[0]-a[1])*(a[1]-a[0])+(a[0]*a[0])+(a[1]*a[1])
* r[10] holds (a[0]*a[0])
* r[32] holds (a[1]*a[1])
* c1 holds the carry bits