0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,
0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,
0xFFFFFFFF,0x000001FF};
-#elif BN_BITS2 == 16
-static const BN_ULONG _nist_p_192[] = {0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFE,
- 0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF};
-static const BN_ULONG _nist_p_224[] = {0x0001,0x0000,0x0000,0x0000,0x0000,
- 0x0000,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF};
-static const BN_ULONG _nist_p_256[] = {0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,
- 0xFFFF,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0001,0x0000,0xFFFF,
- 0xFFFF};
-static const BN_ULONG _nist_p_384[] = {0xFFFF,0xFFFF,0x0000,0x0000,0x0000,
- 0x0000,0xFFFF,0xFFFF,0xFFFE,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,
- 0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF};
-static const BN_ULONG _nist_p_521[] = {0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,
- 0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,
- 0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,
- 0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0xFFFF,0x01FF};
-#elif BN_BITS2 == 8
-static const BN_ULONG _nist_p_192[] = {0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
- 0xFE,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
- 0xFF,0xFF};
-static const BN_ULONG _nist_p_224[] = {0x01,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
- 0x00,0x00,0x00,0x00,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
- 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF};
-static const BN_ULONG _nist_p_256[] = {0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
- 0xFF,0xFF,0xFF,0xFF,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
- 0x00,0x00,0x01,0x00,0x00,0x00,0xFF,0xFF,0xFF,0xFF};
-static const BN_ULONG _nist_p_384[] = {0xFF,0xFF,0xFF,0xFF,0x00,0x00,0x00,0x00,
- 0x00,0x00,0x00,0x00,0xFF,0xFF,0xFF,0xFF,0xFE,0xFF,0xFF,0xFF,0xFF,0xFF,
- 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
- 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF};
-static const BN_ULONG _nist_p_521[] = {0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
- 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
- 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
- 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
- 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
- 0xFF,0x01};
#endif
const BIGNUM *BN_get0_nist_prime_192(void)
return &const_nist_521;
}
-/* some misc internal functions */
-#if BN_BITS2 != 64
-static BN_ULONG _256_data[BN_NIST_256_TOP*6];
-static int _is_set_256_data = 0;
-static void _init_256_data(void);
-
-static BN_ULONG _384_data[BN_NIST_384_TOP*8];
-static int _is_set_384_data = 0;
-static void _init_384_data(void);
-#endif
-
#define BN_NIST_ADD_ONE(a) while (!(*(a)=(*(a)+1)&BN_MASK2)) ++(a);
static void nist_cp_bn_0(BN_ULONG *buf, BN_ULONG *a, int top, int max)
}
#if BN_BITS2 == 64
-#define bn_cp_64(to, n, from, m) (to)[n] = (from)[m];
+#define bn_cp_64(to, n, from, m) (to)[n] = (m>=0)?((from)[m]):0;
#define bn_64_set_0(to, n) (to)[n] = (BN_ULONG)0;
/* TBD */
-#define bn_cp_32(to, n, from, m) (to)[n] = (from)[m];
+#define bn_cp_32(to, n, from, m) (to)[n] = (m>=0)?((from)[m]):0;
#define bn_32_set_0(to, n) (to)[n] = (BN_ULONG)0;
#else
#define bn_cp_64(to, n, from, m) \
bn_32_set_0(to, (n)*2+1); \
}
#if BN_BITS2 == 32
-#define bn_cp_32(to, n, from, m) (to)[n] = (from)[m];
+#define bn_cp_32(to, n, from, m) (to)[n] = (m>=0)?((from)[m]):0;
#define bn_32_set_0(to, n) (to)[n] = (BN_ULONG)0;
-#elif BN_BITS2 == 16
-#define bn_cp_32(to, n, from, m) \
- { \
- (to)[(n)*2] = (from)[(m)*2]; \
- (to)[(n)*2+1] = (from)[(m)*2+1];\
- }
-#define bn_32_set_0(to, n) { (to)[(n)*2] = 0; (to)[(n)*2+1] = 0; }
-#elif BN_BITS2 == 8
-#define bn_cp_32(to, n, from, m) \
- { \
- (to)[(n)*4] = (from)[(m)*4]; \
- (to)[(n)*4+1] = (from)[(m)*4+1];\
- (to)[(n)*4+2] = (from)[(m)*4+2];\
- (to)[(n)*4+3] = (from)[(m)*4+3];\
- }
-#define bn_32_set_0(to, n) \
- { (to)[(n)*4] = (BN_ULONG)0; (to)[(n)*4+1] = (BN_ULONG)0; \
- (to)[(n)*4+2] = (BN_ULONG)0; (to)[(n)*4+3] = (BN_ULONG)0; }
#endif
#endif /* BN_BITS2 != 64 */
BN_CTX *ctx)
{
int top = a->top, i;
+ int carry;
register BN_ULONG *r_d, *a_d = a->d;
BN_ULONG t_d[BN_NIST_192_TOP],
- buf[BN_NIST_192_TOP];
+ buf[BN_NIST_192_TOP],
+ c_d[BN_NIST_192_TOP],
+ *res;
+ size_t mask;
i = BN_ucmp(field, a);
if (i == 0)
nist_cp_bn_0(buf, a_d + BN_NIST_192_TOP, top - BN_NIST_192_TOP, BN_NIST_192_TOP);
-#if defined(OPENSSL_SYS_VMS) && defined(__DECC)
-# pragma message save
-# pragma message disable BADSUBSCRIPT
-#endif
-
nist_set_192(t_d, buf, 0, 3, 3);
- if (bn_add_words(r_d, r_d, t_d, BN_NIST_192_TOP))
- bn_sub_words(r_d, r_d, _nist_p_192, BN_NIST_192_TOP);
-
+ carry = bn_add_words(r_d, r_d, t_d, BN_NIST_192_TOP);
+ mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_192,BN_NIST_192_TOP);
+ mask = ~mask | (0-(size_t)carry);
+ res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask));
+
nist_set_192(t_d, buf, 4, 4, 0);
- if (bn_add_words(r_d, r_d, t_d, BN_NIST_192_TOP))
- bn_sub_words(r_d, r_d, _nist_p_192, BN_NIST_192_TOP);
-
-#if defined(OPENSSL_SYS_VMS) && defined(__DECC)
-# pragma message restore
-#endif
+ carry = bn_add_words(r_d, res, t_d, BN_NIST_192_TOP);
+ mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_192,BN_NIST_192_TOP);
+ mask = ~mask | (0-(size_t)carry);
+ res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask));
nist_set_192(t_d, buf, 5, 5, 5)
- if (bn_add_words(r_d, r_d, t_d, BN_NIST_192_TOP))
- bn_sub_words(r_d, r_d, _nist_p_192, BN_NIST_192_TOP);
+ carry = bn_add_words(r_d, res, t_d, BN_NIST_192_TOP);
+ mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_192,BN_NIST_192_TOP);
+ mask = ~mask | (0-(size_t)carry);
+ res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask));
+ nist_cp_bn(r_d, res, BN_NIST_192_TOP);
r->top = BN_NIST_192_TOP;
bn_correct_top(r);
- if (BN_ucmp(r, field) >= 0)
- {
- bn_sub_words(r_d, r_d, _nist_p_192, BN_NIST_192_TOP);
- bn_correct_top(r);
- }
- bn_check_top(r);
return 1;
}
{
#if BN_BITS2 == 32
int top = a->top, i;
+ int carry;
BN_ULONG *r_d, *a_d = a->d;
BN_ULONG t_d[BN_NIST_224_TOP],
- buf[BN_NIST_224_TOP];
+ buf[BN_NIST_224_TOP],
+ c_d[BN_NIST_224_TOP],
+ *res;
+ size_t mask;
i = BN_ucmp(field, a);
if (i == 0)
nist_cp_bn_0(buf, a_d + BN_NIST_224_TOP, top - BN_NIST_224_TOP, BN_NIST_224_TOP);
nist_set_224(t_d, buf, 10, 9, 8, 7, 0, 0, 0);
- if (bn_add_words(r_d, r_d, t_d, BN_NIST_224_TOP))
- bn_sub_words(r_d,r_d,_nist_p_224,BN_NIST_224_TOP);
+ carry = bn_add_words(r_d, r_d, t_d, BN_NIST_224_TOP);
+ mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_224,BN_NIST_224_TOP);
+ mask = ~mask | (0-(size_t)carry);
+ res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask));
+
nist_set_224(t_d, buf, 0, 13, 12, 11, 0, 0, 0);
- if (bn_add_words(r_d, r_d, t_d, BN_NIST_224_TOP))
- bn_sub_words(r_d,r_d,_nist_p_224,BN_NIST_224_TOP);
+ carry = bn_add_words(r_d, res, t_d, BN_NIST_224_TOP);
+ mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_224,BN_NIST_224_TOP);
+ mask = ~mask | (0-(size_t)carry);
+ res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask));
+
nist_set_224(t_d, buf, 13, 12, 11, 10, 9, 8, 7);
- if (bn_sub_words(r_d, r_d, t_d, BN_NIST_224_TOP))
+#if BRANCH_FREE
+ carry = bn_sub_words(r_d, res, t_d, BN_NIST_224_TOP);
+ bn_add_words(c_d,r_d,_nist_p_224,BN_NIST_224_TOP);
+ mask = 0-(size_t)carry;
+ res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask));
+#else
+ if (bn_sub_words(r_d, res, t_d, BN_NIST_224_TOP))
bn_add_words(r_d,r_d,_nist_p_224,BN_NIST_224_TOP);
+#endif
nist_set_224(t_d, buf, 0, 0, 0, 0, 13, 12, 11);
+#if BRANCH_FREE
+ carry = bn_sub_words(r_d, res, t_d, BN_NIST_224_TOP);
+ bn_add_words(c_d,r_d,_nist_p_224,BN_NIST_224_TOP);
+ mask = 0-(size_t)carry;
+ res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask));
+
+ nist_cp_bn(r_d, res, BN_NIST_224_TOP);
+#else
if (bn_sub_words(r_d, r_d, t_d, BN_NIST_224_TOP))
bn_add_words(r_d,r_d,_nist_p_224,BN_NIST_224_TOP);
-
+#endif
r->top = BN_NIST_224_TOP;
bn_correct_top(r);
- if (BN_ucmp(r, field) >= 0)
- {
- bn_sub_words(r_d, r_d, _nist_p_224, BN_NIST_224_TOP);
- bn_correct_top(r);
- }
- bn_check_top(r);
+
return 1;
-#else
+#else /* BN_BITS!=32 */
return 0;
#endif
}
-#if BN_BITS2 == 32
-static void _init_256_data(void)
- {
- int i;
- BN_ULONG *tmp1 = _256_data;
- const BN_ULONG *tmp2 = tmp1;
-
- memcpy(tmp1, _nist_p_256, BN_NIST_256_TOP * sizeof(BN_ULONG));
- tmp1 += BN_NIST_256_TOP;
-
- for (i=0; i<5; i++)
- {
- bn_add_words(tmp1, _nist_p_256, tmp2, BN_NIST_256_TOP);
- tmp2 = tmp1;
- tmp1 += BN_NIST_256_TOP;
- }
- _is_set_256_data = 1;
- }
-#endif
-
#define nist_set_256(to, from, a1, a2, a3, a4, a5, a6, a7, a8) \
{ \
if (a8 != 0) bn_cp_32(to, 0, from, (a8) - 8) else bn_32_set_0(to, 0)\
int carry = 0;
register BN_ULONG *a_d = a->d, *r_d;
BN_ULONG t_d[BN_NIST_256_TOP],
- t_d2[BN_NIST_256_TOP],
- buf[BN_NIST_256_TOP];
+ buf[BN_NIST_256_TOP],
+ c_d[BN_NIST_256_TOP],
+ *res;
+ size_t mask;
- if (!_is_set_256_data)
- {
- CRYPTO_w_lock(CRYPTO_LOCK_BN);
-
- if (!_is_set_256_data)
- _init_256_data();
-
- CRYPTO_w_unlock(CRYPTO_LOCK_BN);
- }
-
i = BN_ucmp(field, a);
if (i == 0)
{
/*S1*/
nist_set_256(t_d, buf, 15, 14, 13, 12, 11, 0, 0, 0);
/*S2*/
- nist_set_256(t_d2,buf, 0, 15, 14, 13, 12, 0, 0, 0);
- carry = bn_add_words(t_d, t_d, t_d2, BN_NIST_256_TOP);
- /* left shift */
- {
- register BN_ULONG *ap,t,c;
- ap = t_d;
- c=0;
- for (i = BN_NIST_256_TOP; i != 0; --i)
- {
- t= *ap;
- *(ap++)=((t<<1)|c)&BN_MASK2;
- c=(t & BN_TBIT)?1:0;
- }
- carry <<= 1;
- carry |= c;
- }
+ nist_set_256(c_d,buf, 0, 15, 14, 13, 12, 0, 0, 0);
+ carry = bn_add_words(t_d, t_d, c_d, BN_NIST_256_TOP);
+ mask = 0-(size_t)bn_sub_words(c_d,t_d,_nist_p_256,BN_NIST_256_TOP);
+ mask = ~mask | (0-(size_t)carry);
+ res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)t_d&~mask));
+
+ carry = bn_add_words(t_d, res, res, BN_NIST_256_TOP);
+ mask = 0-(size_t)bn_sub_words(c_d,t_d,_nist_p_256,BN_NIST_256_TOP);
+ mask = ~mask | (0-(size_t)carry);
+ res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)t_d&~mask));
+
+ carry = bn_add_words(r_d, r_d, res, BN_NIST_256_TOP);
+ mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_256,BN_NIST_256_TOP);
+ mask = ~mask | (0-(size_t)carry);
+ res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask));
- carry += bn_add_words(r_d, r_d, t_d, BN_NIST_256_TOP);
/*S3*/
nist_set_256(t_d, buf, 15, 14, 0, 0, 0, 10, 9, 8);
- carry += bn_add_words(r_d, r_d, t_d, BN_NIST_256_TOP);
+ carry = bn_add_words(r_d, res, t_d, BN_NIST_256_TOP);
+ mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_256,BN_NIST_256_TOP);
+ mask = ~mask | (0-(size_t)carry);
+ res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask));
+
/*S4*/
nist_set_256(t_d, buf, 8, 13, 15, 14, 13, 11, 10, 9);
- carry += bn_add_words(r_d, r_d, t_d, BN_NIST_256_TOP);
-
- if (carry)
- bn_sub_words(r_d, r_d, _256_data + BN_NIST_256_TOP *
- (carry-1), BN_NIST_256_TOP);
+ carry = bn_add_words(r_d, res, t_d, BN_NIST_256_TOP);
+ mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_256,BN_NIST_256_TOP);
+ mask = ~mask | (0-(size_t)carry);
+ res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask));
/*D1*/
nist_set_256(t_d, buf, 10, 8, 0, 0, 0, 13, 12, 11);
- carry = bn_sub_words(r_d, r_d, t_d, BN_NIST_256_TOP);
+#if BRANCH_FREE
+ carry = bn_sub_words(r_d, res, t_d, BN_NIST_256_TOP);
+ bn_add_words(c_d,r_d,_nist_p_256,BN_NIST_256_TOP);
+ mask = 0-(size_t)carry;
+ res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask));
+#else
+ if (bn_sub_words(r_d, res, t_d, BN_NIST_256_TOP))
+ bn_add_words(r_d,r_d,_nist_p_256,BN_NIST_256_TOP);
+#endif
/*D2*/
nist_set_256(t_d, buf, 11, 9, 0, 0, 15, 14, 13, 12);
- carry += bn_sub_words(r_d, r_d, t_d, BN_NIST_256_TOP);
+#if BRANCH_FREE
+ carry = bn_sub_words(r_d, res, t_d, BN_NIST_256_TOP);
+ bn_add_words(c_d,r_d,_nist_p_256,BN_NIST_256_TOP);
+ mask = 0-(size_t)carry;
+ res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask));
+#else
+ if (bn_sub_words(r_d, r_d, t_d, BN_NIST_256_TOP))
+ bn_add_words(r_d,r_d,_nist_p_256,BN_NIST_256_TOP);
+#endif
/*D3*/
nist_set_256(t_d, buf, 12, 0, 10, 9, 8, 15, 14, 13);
- carry += bn_sub_words(r_d, r_d, t_d, BN_NIST_256_TOP);
+#if BRANCH_FREE
+ carry = bn_sub_words(r_d, res, t_d, BN_NIST_256_TOP);
+ bn_add_words(c_d,r_d,_nist_p_256,BN_NIST_256_TOP);
+ mask = 0-(size_t)carry;
+ res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask));
+#else
+ if (bn_sub_words(r_d, r_d, t_d, BN_NIST_256_TOP))
+ bn_add_words(r_d,r_d,_nist_p_256,BN_NIST_256_TOP);
+#endif
/*D4*/
nist_set_256(t_d, buf, 13, 0, 11, 10, 9, 0, 15, 14);
- carry += bn_sub_words(r_d, r_d, t_d, BN_NIST_256_TOP);
-
- if (carry)
- bn_add_words(r_d, r_d, _256_data + BN_NIST_256_TOP *
- (carry-1), BN_NIST_256_TOP);
+#if BRANCH_FREE
+ carry = bn_sub_words(r_d, res, t_d, BN_NIST_256_TOP);
+ bn_add_words(c_d,r_d,_nist_p_256,BN_NIST_256_TOP);
+ mask = 0-(size_t)carry;
+ res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask));
+ nist_cp_bn(r_d, res, BN_NIST_384_TOP);
+#else
+ if (bn_sub_words(r_d, r_d, t_d, BN_NIST_256_TOP))
+ bn_add_words(r_d,r_d,_nist_p_256,BN_NIST_256_TOP);
+#endif
r->top = BN_NIST_256_TOP;
bn_correct_top(r);
- if (BN_ucmp(r, field) >= 0)
- {
- bn_sub_words(r_d, r_d, _nist_p_256, BN_NIST_256_TOP);
- bn_correct_top(r);
- }
- bn_check_top(r);
+
return 1;
-#else
+#else /* BN_BITS!=32 */
return 0;
#endif
}
-#if BN_BITS2 == 32
-static void _init_384_data(void)
- {
- int i;
- BN_ULONG *tmp1 = _384_data;
- const BN_ULONG *tmp2 = tmp1;
-
- memcpy(tmp1, _nist_p_384, BN_NIST_384_TOP * sizeof(BN_ULONG));
- tmp1 += BN_NIST_384_TOP;
-
- for (i=0; i<7; i++)
- {
- bn_add_words(tmp1, _nist_p_384, tmp2, BN_NIST_384_TOP);
- tmp2 = tmp1;
- tmp1 += BN_NIST_384_TOP;
- }
- _is_set_384_data = 1;
- }
-#endif
-
#define nist_set_384(to,from,a1,a2,a3,a4,a5,a6,a7,a8,a9,a10,a11,a12) \
{ \
if (a12 != 0) bn_cp_32(to, 0, from, (a12) - 12) else bn_32_set_0(to, 0)\
int carry = 0;
register BN_ULONG *r_d, *a_d = a->d;
BN_ULONG t_d[BN_NIST_384_TOP],
- buf[BN_NIST_384_TOP];
-
- if (!_is_set_384_data)
- {
- CRYPTO_w_lock(CRYPTO_LOCK_BN);
-
- if (!_is_set_384_data)
- _init_384_data();
-
- CRYPTO_w_unlock(CRYPTO_LOCK_BN);
- }
+ buf[BN_NIST_384_TOP],
+ c_d[BN_NIST_384_TOP],
+ *res;
+ size_t mask;
i = BN_ucmp(field, a);
if (i == 0)
}
carry = bn_add_words(r_d+(128/BN_BITS2), r_d+(128/BN_BITS2),
t_d, BN_NIST_256_TOP);
+ /*
+ * we need if (result>=modulus) subtract(result,modulus);
+ * in n-bit space this can be expressed as
+ * if (carry || result>=modulus) subtract(result,modulus);
+ * the catch is that comparison implies subtraction and
+ * therefore one can write tmp=subtract(result,modulus);
+ * and then if(carry || !borrow) result=tmp; this's what
+ * happens below, but without explicit if:-) a.
+ */
+ mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_384,BN_NIST_384_TOP);
+ mask = ~mask | (0-(size_t)carry);
+ res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask));
+
/*S2 */
- carry += bn_add_words(r_d, r_d, buf, BN_NIST_384_TOP);
+ carry = bn_add_words(r_d, res, buf, BN_NIST_384_TOP);
+ mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_384,BN_NIST_384_TOP);
+ mask = ~mask | (0-(size_t)carry);
+ res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask));
+
/*S3*/
nist_set_384(t_d,buf,20,19,18,17,16,15,14,13,12,23,22,21);
- carry += bn_add_words(r_d, r_d, t_d, BN_NIST_384_TOP);
+ carry = bn_add_words(r_d, res, t_d, BN_NIST_384_TOP);
+ mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_384,BN_NIST_384_TOP);
+ mask = ~mask | (0-(size_t)carry);
+ res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask));
+
/*S4*/
nist_set_384(t_d,buf,19,18,17,16,15,14,13,12,20,0,23,0);
- carry += bn_add_words(r_d, r_d, t_d, BN_NIST_384_TOP);
+ carry = bn_add_words(r_d, res, t_d, BN_NIST_384_TOP);
+ mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_384,BN_NIST_384_TOP);
+ mask = ~mask | (0-(size_t)carry);
+ res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask));
+
/*S5*/
- nist_set_256(t_d, buf, 0, 0, 0, 0, 23-4, 22-4, 21-4, 20-4);
- carry += bn_add_words(r_d+(128/BN_BITS2), r_d+(128/BN_BITS2),
- t_d, BN_NIST_256_TOP);
+ nist_set_384(t_d, buf,0,0,0,0,23,22,21,20,0,0,0,0);
+ carry = bn_add_words(r_d, res, t_d, BN_NIST_384_TOP);
+ mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_384,BN_NIST_384_TOP);
+ mask = ~mask | (0-(size_t)carry);
+ res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask));
+
/*S6*/
nist_set_384(t_d,buf,0,0,0,0,0,0,23,22,21,0,0,20);
- carry += bn_add_words(r_d, r_d, t_d, BN_NIST_384_TOP);
-
- if (carry)
- bn_sub_words(r_d, r_d, _384_data + BN_NIST_384_TOP *
- (carry-1), BN_NIST_384_TOP);
+ carry = bn_add_words(r_d, res, t_d, BN_NIST_384_TOP);
+ mask = 0-(size_t)bn_sub_words(c_d,r_d,_nist_p_384,BN_NIST_384_TOP);
+ mask = ~mask | (0-(size_t)carry);
+ res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask));
/*D1*/
nist_set_384(t_d,buf,22,21,20,19,18,17,16,15,14,13,12,23);
- carry = bn_sub_words(r_d, r_d, t_d, BN_NIST_384_TOP);
+#if BRANCH_FREE
+ carry = bn_sub_words(r_d, res, t_d, BN_NIST_384_TOP);
+ bn_add_words(c_d,r_d,_nist_p_384,BN_NIST_384_TOP);
+ mask = 0-(size_t)carry;
+ res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask));
+#else
+ if (bn_sub_words(r_d, res, t_d, BN_NIST_384_TOP))
+ bn_add_words(r_d,r_d,_nist_p_384,BN_NIST_384_TOP);
+#endif
/*D2*/
nist_set_384(t_d,buf,0,0,0,0,0,0,0,23,22,21,20,0);
- carry += bn_sub_words(r_d, r_d, t_d, BN_NIST_384_TOP);
+#if BRANCH_FREE
+ carry = bn_sub_words(r_d, res, t_d, BN_NIST_384_TOP);
+ bn_add_words(c_d,r_d,_nist_p_384,BN_NIST_384_TOP);
+ mask = 0-(size_t)carry;
+ res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask));
+#else
+ if (bn_sub_words(r_d, r_d, t_d, BN_NIST_384_TOP))
+ bn_add_words(r_d,r_d,_nist_p_384,BN_NIST_384_TOP);
+#endif
/*D3*/
nist_set_384(t_d,buf,0,0,0,0,0,0,0,23,23,0,0,0);
- carry += bn_sub_words(r_d, r_d, t_d, BN_NIST_384_TOP);
-
- if (carry)
- bn_add_words(r_d, r_d, _384_data + BN_NIST_384_TOP *
- (carry-1), BN_NIST_384_TOP);
+#if BRANCH_FREE
+ carry = bn_sub_words(r_d, res, t_d, BN_NIST_384_TOP);
+ bn_add_words(c_d,r_d,_nist_p_384,BN_NIST_384_TOP);
+ mask = 0-(size_t)carry;
+ res = (BN_ULONG *)(((size_t)c_d&mask) | ((size_t)r_d&~mask));
+ nist_cp_bn(r_d, res, BN_NIST_384_TOP);
+#else
+ if (bn_sub_words(r_d, r_d, t_d, BN_NIST_384_TOP))
+ bn_add_words(r_d,r_d,_nist_p_384,BN_NIST_384_TOP);
+#endif
r->top = BN_NIST_384_TOP;
bn_correct_top(r);
- if (BN_ucmp(r, field) >= 0)
- {
- bn_sub_words(r_d, r_d, _nist_p_384, BN_NIST_384_TOP);
- bn_correct_top(r);
- }
- bn_check_top(r);
+
return 1;
-#else
+#else /* BN_BITS!=32 */
return 0;
#endif
}
#define BN_NIST_521_TOP_MASK (BN_ULONG)0x1FF
#elif BN_BITS2 == 32
#define BN_NIST_521_TOP_MASK (BN_ULONG)0x1FF
-#elif BN_BITS2 == 16
-#define BN_NIST_521_TOP_MASK (BN_ULONG)0x1FF
-#elif BN_BITS2 == 8
-#define BN_NIST_521_TOP_MASK (BN_ULONG)0x1
#endif
int top, ret = 0;
BN_ULONG *r_d;