#include "cryptlib.h"
#include "bn_lcl.h"
-int BN_lshift1(BIGNUM *r, BIGNUM *a)
+int BN_lshift1(BIGNUM *r, const BIGNUM *a)
{
register BN_ULONG *ap,*rp,t,c;
int i;
return(1);
}
-int BN_rshift1(BIGNUM *r, BIGNUM *a)
+int BN_rshift1(BIGNUM *r, const BIGNUM *a)
{
BN_ULONG *ap,*rp,t,c;
int i;
BN_ULONG l;
r->neg=a->neg;
- if (bn_wexpand(r,a->top+(n/BN_BITS2)+1) == NULL) return(0);
nw=n/BN_BITS2;
+ if (bn_wexpand(r,a->top+nw+1) == NULL) return(0);
lb=n%BN_BITS2;
rb=BN_BITS2-lb;
f=a->d;
return(1);
}
-int BN_rshift(BIGNUM *r, BIGNUM *a, int n)
+int BN_rshift(BIGNUM *r, const BIGNUM *a, int n)
{
int i,j,nw,lb,rb;
BN_ULONG *t,*f;
nw=n/BN_BITS2;
rb=n%BN_BITS2;
lb=BN_BITS2-rb;
- if (nw > a->top)
+ if (nw > a->top || a->top == 0)
{
BN_zero(r);
return(1);
r->neg=a->neg;
if (bn_wexpand(r,a->top-nw+1) == NULL) return(0);
}
+ else
+ {
+ if (n == 0)
+ return 1; /* or the copying loop will go berserk */
+ }
f= &(a->d[nw]);
t=r->d;