*
*/
-#define OPENSSL_FIPSAPI
+
#include "cryptlib.h"
#include "bn_lcl.h"
bn_check_top(p);
bn_check_top(m);
- /* For even modulus m = 2^k*m_odd, it might make sense to compute
+ /*-
+ * For even modulus m = 2^k*m_odd, it might make sense to compute
* a^p mod m_odd and a^p mod 2^k separately (with Montgomery
* exponentiation for the odd part), using appropriate exponent
* reductions, and combine the results using the CRT.
* the top bit being set. It was caused by an error in BN_div
* with negatives. There was also another problem when for a^b%m
* a >= m. eay 07-May-97 */
-/* if ((m->d[m->top-1]&BN_TBIT) && BN_is_odd(m)) */
+ /* if ((m->d[m->top-1]&BN_TBIT) && BN_is_odd(m)) */
if (BN_is_odd(m))
{
r->d[0] = (0-m->d[0])&BN_MASK2;
for(i=1;i<j;i++) r->d[i] = (~m->d[i])&BN_MASK2;
r->top = j;
+ /* Upper words will be zero if the corresponding words of 'm'
+ * were 0xfff[...], so decrement r->top accordingly. */
+ bn_correct_top(r);
}
else
#endif
else
#endif
#if defined(OPENSSL_BN_ASM_MONT5)
- if (window==6 && bits<=1024) window=5; /* ~5% improvement of 2048-bit RSA sign */
+ if (window>=5)
+ {
+ window=5; /* ~5% improvement for RSA2048 sign, and even for RSA4096 */
+ if ((top&7)==0) powerbufLen += 2*top*sizeof(m->d[0]);
+ }
#endif
(void)0;
* powers of am, am itself and tmp.
*/
numPowers = 1 << window;
- powerbufLen = sizeof(m->d[0])*(top*numPowers +
+ powerbufLen += sizeof(m->d[0])*(top*numPowers +
((2*top)>numPowers?(2*top):numPowers));
#ifdef alloca
if (powerbufLen < 3072)
else
#endif
#if defined(OPENSSL_BN_ASM_MONT5)
- /* This optimization uses ideas from http://eprint.iacr.org/2011/239,
- * specifically optimization of cache-timing attack countermeasures
- * and pre-computation optimization. */
-
- /* Dedicated window==4 case improves 512-bit RSA sign by ~15%, but as
- * 512-bit RSA is hardly relevant, we omit it to spare size... */
- if (window==5)
+ if (window==5 && top>1)
{
+ /* This optimization uses ideas from http://eprint.iacr.org/2011/239,
+ * specifically optimization of cache-timing attack countermeasures
+ * and pre-computation optimization. */
+
+ /* Dedicated window==4 case improves 512-bit RSA sign by ~15%, but as
+ * 512-bit RSA is hardly relevant, we omit it to spare size... */
void bn_mul_mont_gather5(BN_ULONG *rp,const BN_ULONG *ap,
const void *table,const BN_ULONG *np,
const BN_ULONG *n0,int num,int power);
void *table,size_t power);
void bn_gather5(BN_ULONG *out,size_t num,
void *table,size_t power);
+ void bn_power5(BN_ULONG *rp,const BN_ULONG *ap,
+ const void *table,const BN_ULONG *np,
+ const BN_ULONG *n0,int num,int power);
+ int bn_get_bits5(const BN_ULONG *ap,int off);
+ int bn_from_montgomery(BN_ULONG *rp,const BN_ULONG *ap,
+ const BN_ULONG *not_used,const BN_ULONG *np,
+ const BN_ULONG *n0,int num);
- BN_ULONG *np=mont->N.d, *n0=mont->n0;
+ BN_ULONG *np=mont->N.d, *n0=mont->n0, *np2;
/* BN_to_montgomery can contaminate words above .top
* [in BN_DEBUG[_DEBUG] build]... */
for (i=am.top; i<top; i++) am.d[i]=0;
for (i=tmp.top; i<top; i++) tmp.d[i]=0;
+ if (top&7)
+ np2 = np;
+ else
+ for (np2=am.d+top,i=0; i<top; i++) np2[2*i]=np[i];
+
bn_scatter5(tmp.d,top,powerbuf,0);
bn_scatter5(am.d,am.top,powerbuf,1);
bn_mul_mont(tmp.d,am.d,am.d,np,n0,top);
for (i=3; i<32; i++)
{
/* Calculate a^i = a^(i-1) * a */
- bn_mul_mont_gather5(tmp.d,am.d,powerbuf,np,n0,top,i-1);
+ bn_mul_mont_gather5(tmp.d,am.d,powerbuf,np2,n0,top,i-1);
bn_scatter5(tmp.d,top,powerbuf,i);
}
#else
for (i=3; i<8; i+=2)
{
int j;
- bn_mul_mont_gather5(tmp.d,am.d,powerbuf,np,n0,top,i-1);
+ bn_mul_mont_gather5(tmp.d,am.d,powerbuf,np2,n0,top,i-1);
bn_scatter5(tmp.d,top,powerbuf,i);
for (j=2*i; j<32; j*=2)
{
}
for (; i<16; i+=2)
{
- bn_mul_mont_gather5(tmp.d,am.d,powerbuf,np,n0,top,i-1);
+ bn_mul_mont_gather5(tmp.d,am.d,powerbuf,np2,n0,top,i-1);
bn_scatter5(tmp.d,top,powerbuf,i);
bn_mul_mont(tmp.d,tmp.d,tmp.d,np,n0,top);
bn_scatter5(tmp.d,top,powerbuf,2*i);
}
for (; i<32; i+=2)
{
- bn_mul_mont_gather5(tmp.d,am.d,powerbuf,np,n0,top,i-1);
+ bn_mul_mont_gather5(tmp.d,am.d,powerbuf,np2,n0,top,i-1);
bn_scatter5(tmp.d,top,powerbuf,i);
}
#endif
/* Scan the exponent one window at a time starting from the most
* significant bits.
*/
- while (bits >= 0)
+ if (top&7)
+ while (bits >= 0)
{
for (wvalue=0, i=0; i<5; i++,bits--)
wvalue = (wvalue<<1)+BN_is_bit_set(p,bits);
bn_mul_mont(tmp.d,tmp.d,tmp.d,np,n0,top);
bn_mul_mont_gather5(tmp.d,tmp.d,powerbuf,np,n0,top,wvalue);
}
+ else
+ {
+ while (bits >= 0)
+ {
+ wvalue = bn_get_bits5(p->d,bits-4);
+ bits-=5;
+ bn_power5(tmp.d,tmp.d,powerbuf,np2,n0,top,wvalue);
+ }
+ }
+ ret=bn_from_montgomery(tmp.d,tmp.d,NULL,np2,n0,top);
tmp.top=top;
bn_correct_top(&tmp);
+ if (ret)
+ {
+ if (!BN_copy(rr,&tmp)) ret=0;
+ goto err; /* non-zero ret means it's not error */
+ }
}
else
#endif