2 * Copyright 2014-2018 The OpenSSL Project Authors. All Rights Reserved.
3 * Copyright (c) 2014, Intel Corporation. All Rights Reserved.
4 * Copyright (c) 2015, CloudFlare, Inc.
6 * Licensed under the Apache License 2.0 (the "License"). You may not use
7 * this file except in compliance with the License. You can obtain a copy
8 * in the file LICENSE in the source distribution or at
9 * https://www.openssl.org/source/license.html
11 * Originally written by Shay Gueron (1, 2), and Vlad Krasnov (1, 3)
12 * (1) Intel Corporation, Israel Development Center, Haifa, Israel
13 * (2) University of Haifa, Israel
14 * (3) CloudFlare, Inc.
17 * S.Gueron and V.Krasnov, "Fast Prime Field Elliptic Curve Cryptography with
23 #include "internal/cryptlib.h"
24 #include "internal/bn_int.h"
26 #include "internal/refcount.h"
29 # define TOBN(hi,lo) lo,hi
31 # define TOBN(hi,lo) ((BN_ULONG)hi<<32|lo)
35 # define ALIGN32 __attribute((aligned(32)))
36 #elif defined(_MSC_VER)
37 # define ALIGN32 __declspec(align(32))
42 #define ALIGNPTR(p,N) ((unsigned char *)p+N-(size_t)p%N)
43 #define P256_LIMBS (256/BN_BITS2)
45 typedef unsigned short u16
;
48 BN_ULONG X
[P256_LIMBS
];
49 BN_ULONG Y
[P256_LIMBS
];
50 BN_ULONG Z
[P256_LIMBS
];
54 BN_ULONG X
[P256_LIMBS
];
55 BN_ULONG Y
[P256_LIMBS
];
58 typedef P256_POINT_AFFINE PRECOMP256_ROW
[64];
60 /* structure for precomputed multiples of the generator */
61 struct nistz256_pre_comp_st
{
62 const EC_GROUP
*group
; /* Parent EC_GROUP object */
63 size_t w
; /* Window size */
65 * Constant time access to the X and Y coordinates of the pre-computed,
66 * generator multiplies, in the Montgomery domain. Pre-calculated
67 * multiplies are stored in affine form.
69 PRECOMP256_ROW
*precomp
;
70 void *precomp_storage
;
71 CRYPTO_REF_COUNT references
;
75 /* Functions implemented in assembly */
77 * Most of below mentioned functions *preserve* the property of inputs
78 * being fully reduced, i.e. being in [0, modulus) range. Simply put if
79 * inputs are fully reduced, then output is too. Note that reverse is
80 * not true, in sense that given partially reduced inputs output can be
81 * either, not unlikely reduced. And "most" in first sentence refers to
82 * the fact that given the calculations flow one can tolerate that
83 * addition, 1st function below, produces partially reduced result *if*
84 * multiplications by 2 and 3, which customarily use addition, fully
85 * reduce it. This effectively gives two options: a) addition produces
86 * fully reduced result [as long as inputs are, just like remaining
87 * functions]; b) addition is allowed to produce partially reduced
88 * result, but multiplications by 2 and 3 perform additional reduction
89 * step. Choice between the two can be platform-specific, but it was a)
90 * in all cases so far...
92 /* Modular add: res = a+b mod P */
93 void ecp_nistz256_add(BN_ULONG res
[P256_LIMBS
],
94 const BN_ULONG a
[P256_LIMBS
],
95 const BN_ULONG b
[P256_LIMBS
]);
96 /* Modular mul by 2: res = 2*a mod P */
97 void ecp_nistz256_mul_by_2(BN_ULONG res
[P256_LIMBS
],
98 const BN_ULONG a
[P256_LIMBS
]);
99 /* Modular mul by 3: res = 3*a mod P */
100 void ecp_nistz256_mul_by_3(BN_ULONG res
[P256_LIMBS
],
101 const BN_ULONG a
[P256_LIMBS
]);
103 /* Modular div by 2: res = a/2 mod P */
104 void ecp_nistz256_div_by_2(BN_ULONG res
[P256_LIMBS
],
105 const BN_ULONG a
[P256_LIMBS
]);
106 /* Modular sub: res = a-b mod P */
107 void ecp_nistz256_sub(BN_ULONG res
[P256_LIMBS
],
108 const BN_ULONG a
[P256_LIMBS
],
109 const BN_ULONG b
[P256_LIMBS
]);
110 /* Modular neg: res = -a mod P */
111 void ecp_nistz256_neg(BN_ULONG res
[P256_LIMBS
], const BN_ULONG a
[P256_LIMBS
]);
112 /* Montgomery mul: res = a*b*2^-256 mod P */
113 void ecp_nistz256_mul_mont(BN_ULONG res
[P256_LIMBS
],
114 const BN_ULONG a
[P256_LIMBS
],
115 const BN_ULONG b
[P256_LIMBS
]);
116 /* Montgomery sqr: res = a*a*2^-256 mod P */
117 void ecp_nistz256_sqr_mont(BN_ULONG res
[P256_LIMBS
],
118 const BN_ULONG a
[P256_LIMBS
]);
119 /* Convert a number from Montgomery domain, by multiplying with 1 */
120 void ecp_nistz256_from_mont(BN_ULONG res
[P256_LIMBS
],
121 const BN_ULONG in
[P256_LIMBS
]);
122 /* Convert a number to Montgomery domain, by multiplying with 2^512 mod P*/
123 void ecp_nistz256_to_mont(BN_ULONG res
[P256_LIMBS
],
124 const BN_ULONG in
[P256_LIMBS
]);
125 /* Functions that perform constant time access to the precomputed tables */
126 void ecp_nistz256_scatter_w5(P256_POINT
*val
,
127 const P256_POINT
*in_t
, int idx
);
128 void ecp_nistz256_gather_w5(P256_POINT
*val
,
129 const P256_POINT
*in_t
, int idx
);
130 void ecp_nistz256_scatter_w7(P256_POINT_AFFINE
*val
,
131 const P256_POINT_AFFINE
*in_t
, int idx
);
132 void ecp_nistz256_gather_w7(P256_POINT_AFFINE
*val
,
133 const P256_POINT_AFFINE
*in_t
, int idx
);
135 /* One converted into the Montgomery domain */
136 static const BN_ULONG ONE
[P256_LIMBS
] = {
137 TOBN(0x00000000, 0x00000001), TOBN(0xffffffff, 0x00000000),
138 TOBN(0xffffffff, 0xffffffff), TOBN(0x00000000, 0xfffffffe)
141 static NISTZ256_PRE_COMP
*ecp_nistz256_pre_comp_new(const EC_GROUP
*group
);
143 /* Precomputed tables for the default generator */
144 extern const PRECOMP256_ROW ecp_nistz256_precomputed
[37];
146 /* Recode window to a signed digit, see ecp_nistputil.c for details */
147 static unsigned int _booth_recode_w5(unsigned int in
)
151 s
= ~((in
>> 5) - 1);
152 d
= (1 << 6) - in
- 1;
153 d
= (d
& s
) | (in
& ~s
);
154 d
= (d
>> 1) + (d
& 1);
156 return (d
<< 1) + (s
& 1);
159 static unsigned int _booth_recode_w7(unsigned int in
)
163 s
= ~((in
>> 7) - 1);
164 d
= (1 << 8) - in
- 1;
165 d
= (d
& s
) | (in
& ~s
);
166 d
= (d
>> 1) + (d
& 1);
168 return (d
<< 1) + (s
& 1);
171 static void copy_conditional(BN_ULONG dst
[P256_LIMBS
],
172 const BN_ULONG src
[P256_LIMBS
], BN_ULONG move
)
174 BN_ULONG mask1
= 0-move
;
175 BN_ULONG mask2
= ~mask1
;
177 dst
[0] = (src
[0] & mask1
) ^ (dst
[0] & mask2
);
178 dst
[1] = (src
[1] & mask1
) ^ (dst
[1] & mask2
);
179 dst
[2] = (src
[2] & mask1
) ^ (dst
[2] & mask2
);
180 dst
[3] = (src
[3] & mask1
) ^ (dst
[3] & mask2
);
181 if (P256_LIMBS
== 8) {
182 dst
[4] = (src
[4] & mask1
) ^ (dst
[4] & mask2
);
183 dst
[5] = (src
[5] & mask1
) ^ (dst
[5] & mask2
);
184 dst
[6] = (src
[6] & mask1
) ^ (dst
[6] & mask2
);
185 dst
[7] = (src
[7] & mask1
) ^ (dst
[7] & mask2
);
189 static BN_ULONG
is_zero(BN_ULONG in
)
197 static BN_ULONG
is_equal(const BN_ULONG a
[P256_LIMBS
],
198 const BN_ULONG b
[P256_LIMBS
])
206 if (P256_LIMBS
== 8) {
216 static BN_ULONG
is_one(const BIGNUM
*z
)
219 BN_ULONG
*a
= bn_get_words(z
);
221 if (bn_get_top(z
) == (P256_LIMBS
- P256_LIMBS
/ 8)) {
223 res
|= a
[1] ^ ONE
[1];
224 res
|= a
[2] ^ ONE
[2];
225 res
|= a
[3] ^ ONE
[3];
226 if (P256_LIMBS
== 8) {
227 res
|= a
[4] ^ ONE
[4];
228 res
|= a
[5] ^ ONE
[5];
229 res
|= a
[6] ^ ONE
[6];
231 * no check for a[7] (being zero) on 32-bit platforms,
232 * because value of "one" takes only 7 limbs.
242 * For reference, this macro is used only when new ecp_nistz256 assembly
243 * module is being developed. For example, configure with
244 * -DECP_NISTZ256_REFERENCE_IMPLEMENTATION and implement only functions
245 * performing simplest arithmetic operations on 256-bit vectors. Then
246 * work on implementation of higher-level functions performing point
247 * operations. Then remove ECP_NISTZ256_REFERENCE_IMPLEMENTATION
248 * and never define it again. (The correct macro denoting presence of
249 * ecp_nistz256 module is ECP_NISTZ256_ASM.)
251 #ifndef ECP_NISTZ256_REFERENCE_IMPLEMENTATION
252 void ecp_nistz256_point_double(P256_POINT
*r
, const P256_POINT
*a
);
253 void ecp_nistz256_point_add(P256_POINT
*r
,
254 const P256_POINT
*a
, const P256_POINT
*b
);
255 void ecp_nistz256_point_add_affine(P256_POINT
*r
,
257 const P256_POINT_AFFINE
*b
);
259 /* Point double: r = 2*a */
260 static void ecp_nistz256_point_double(P256_POINT
*r
, const P256_POINT
*a
)
262 BN_ULONG S
[P256_LIMBS
];
263 BN_ULONG M
[P256_LIMBS
];
264 BN_ULONG Zsqr
[P256_LIMBS
];
265 BN_ULONG tmp0
[P256_LIMBS
];
267 const BN_ULONG
*in_x
= a
->X
;
268 const BN_ULONG
*in_y
= a
->Y
;
269 const BN_ULONG
*in_z
= a
->Z
;
271 BN_ULONG
*res_x
= r
->X
;
272 BN_ULONG
*res_y
= r
->Y
;
273 BN_ULONG
*res_z
= r
->Z
;
275 ecp_nistz256_mul_by_2(S
, in_y
);
277 ecp_nistz256_sqr_mont(Zsqr
, in_z
);
279 ecp_nistz256_sqr_mont(S
, S
);
281 ecp_nistz256_mul_mont(res_z
, in_z
, in_y
);
282 ecp_nistz256_mul_by_2(res_z
, res_z
);
284 ecp_nistz256_add(M
, in_x
, Zsqr
);
285 ecp_nistz256_sub(Zsqr
, in_x
, Zsqr
);
287 ecp_nistz256_sqr_mont(res_y
, S
);
288 ecp_nistz256_div_by_2(res_y
, res_y
);
290 ecp_nistz256_mul_mont(M
, M
, Zsqr
);
291 ecp_nistz256_mul_by_3(M
, M
);
293 ecp_nistz256_mul_mont(S
, S
, in_x
);
294 ecp_nistz256_mul_by_2(tmp0
, S
);
296 ecp_nistz256_sqr_mont(res_x
, M
);
298 ecp_nistz256_sub(res_x
, res_x
, tmp0
);
299 ecp_nistz256_sub(S
, S
, res_x
);
301 ecp_nistz256_mul_mont(S
, S
, M
);
302 ecp_nistz256_sub(res_y
, S
, res_y
);
305 /* Point addition: r = a+b */
306 static void ecp_nistz256_point_add(P256_POINT
*r
,
307 const P256_POINT
*a
, const P256_POINT
*b
)
309 BN_ULONG U2
[P256_LIMBS
], S2
[P256_LIMBS
];
310 BN_ULONG U1
[P256_LIMBS
], S1
[P256_LIMBS
];
311 BN_ULONG Z1sqr
[P256_LIMBS
];
312 BN_ULONG Z2sqr
[P256_LIMBS
];
313 BN_ULONG H
[P256_LIMBS
], R
[P256_LIMBS
];
314 BN_ULONG Hsqr
[P256_LIMBS
];
315 BN_ULONG Rsqr
[P256_LIMBS
];
316 BN_ULONG Hcub
[P256_LIMBS
];
318 BN_ULONG res_x
[P256_LIMBS
];
319 BN_ULONG res_y
[P256_LIMBS
];
320 BN_ULONG res_z
[P256_LIMBS
];
322 BN_ULONG in1infty
, in2infty
;
324 const BN_ULONG
*in1_x
= a
->X
;
325 const BN_ULONG
*in1_y
= a
->Y
;
326 const BN_ULONG
*in1_z
= a
->Z
;
328 const BN_ULONG
*in2_x
= b
->X
;
329 const BN_ULONG
*in2_y
= b
->Y
;
330 const BN_ULONG
*in2_z
= b
->Z
;
333 * Infinity in encoded as (,,0)
335 in1infty
= (in1_z
[0] | in1_z
[1] | in1_z
[2] | in1_z
[3]);
337 in1infty
|= (in1_z
[4] | in1_z
[5] | in1_z
[6] | in1_z
[7]);
339 in2infty
= (in2_z
[0] | in2_z
[1] | in2_z
[2] | in2_z
[3]);
341 in2infty
|= (in2_z
[4] | in2_z
[5] | in2_z
[6] | in2_z
[7]);
343 in1infty
= is_zero(in1infty
);
344 in2infty
= is_zero(in2infty
);
346 ecp_nistz256_sqr_mont(Z2sqr
, in2_z
); /* Z2^2 */
347 ecp_nistz256_sqr_mont(Z1sqr
, in1_z
); /* Z1^2 */
349 ecp_nistz256_mul_mont(S1
, Z2sqr
, in2_z
); /* S1 = Z2^3 */
350 ecp_nistz256_mul_mont(S2
, Z1sqr
, in1_z
); /* S2 = Z1^3 */
352 ecp_nistz256_mul_mont(S1
, S1
, in1_y
); /* S1 = Y1*Z2^3 */
353 ecp_nistz256_mul_mont(S2
, S2
, in2_y
); /* S2 = Y2*Z1^3 */
354 ecp_nistz256_sub(R
, S2
, S1
); /* R = S2 - S1 */
356 ecp_nistz256_mul_mont(U1
, in1_x
, Z2sqr
); /* U1 = X1*Z2^2 */
357 ecp_nistz256_mul_mont(U2
, in2_x
, Z1sqr
); /* U2 = X2*Z1^2 */
358 ecp_nistz256_sub(H
, U2
, U1
); /* H = U2 - U1 */
361 * This should not happen during sign/ecdh, so no constant time violation
363 if (is_equal(U1
, U2
) && !in1infty
&& !in2infty
) {
364 if (is_equal(S1
, S2
)) {
365 ecp_nistz256_point_double(r
, a
);
368 memset(r
, 0, sizeof(*r
));
373 ecp_nistz256_sqr_mont(Rsqr
, R
); /* R^2 */
374 ecp_nistz256_mul_mont(res_z
, H
, in1_z
); /* Z3 = H*Z1*Z2 */
375 ecp_nistz256_sqr_mont(Hsqr
, H
); /* H^2 */
376 ecp_nistz256_mul_mont(res_z
, res_z
, in2_z
); /* Z3 = H*Z1*Z2 */
377 ecp_nistz256_mul_mont(Hcub
, Hsqr
, H
); /* H^3 */
379 ecp_nistz256_mul_mont(U2
, U1
, Hsqr
); /* U1*H^2 */
380 ecp_nistz256_mul_by_2(Hsqr
, U2
); /* 2*U1*H^2 */
382 ecp_nistz256_sub(res_x
, Rsqr
, Hsqr
);
383 ecp_nistz256_sub(res_x
, res_x
, Hcub
);
385 ecp_nistz256_sub(res_y
, U2
, res_x
);
387 ecp_nistz256_mul_mont(S2
, S1
, Hcub
);
388 ecp_nistz256_mul_mont(res_y
, R
, res_y
);
389 ecp_nistz256_sub(res_y
, res_y
, S2
);
391 copy_conditional(res_x
, in2_x
, in1infty
);
392 copy_conditional(res_y
, in2_y
, in1infty
);
393 copy_conditional(res_z
, in2_z
, in1infty
);
395 copy_conditional(res_x
, in1_x
, in2infty
);
396 copy_conditional(res_y
, in1_y
, in2infty
);
397 copy_conditional(res_z
, in1_z
, in2infty
);
399 memcpy(r
->X
, res_x
, sizeof(res_x
));
400 memcpy(r
->Y
, res_y
, sizeof(res_y
));
401 memcpy(r
->Z
, res_z
, sizeof(res_z
));
404 /* Point addition when b is known to be affine: r = a+b */
405 static void ecp_nistz256_point_add_affine(P256_POINT
*r
,
407 const P256_POINT_AFFINE
*b
)
409 BN_ULONG U2
[P256_LIMBS
], S2
[P256_LIMBS
];
410 BN_ULONG Z1sqr
[P256_LIMBS
];
411 BN_ULONG H
[P256_LIMBS
], R
[P256_LIMBS
];
412 BN_ULONG Hsqr
[P256_LIMBS
];
413 BN_ULONG Rsqr
[P256_LIMBS
];
414 BN_ULONG Hcub
[P256_LIMBS
];
416 BN_ULONG res_x
[P256_LIMBS
];
417 BN_ULONG res_y
[P256_LIMBS
];
418 BN_ULONG res_z
[P256_LIMBS
];
420 BN_ULONG in1infty
, in2infty
;
422 const BN_ULONG
*in1_x
= a
->X
;
423 const BN_ULONG
*in1_y
= a
->Y
;
424 const BN_ULONG
*in1_z
= a
->Z
;
426 const BN_ULONG
*in2_x
= b
->X
;
427 const BN_ULONG
*in2_y
= b
->Y
;
430 * Infinity in encoded as (,,0)
432 in1infty
= (in1_z
[0] | in1_z
[1] | in1_z
[2] | in1_z
[3]);
434 in1infty
|= (in1_z
[4] | in1_z
[5] | in1_z
[6] | in1_z
[7]);
437 * In affine representation we encode infinity as (0,0), which is
438 * not on the curve, so it is OK
440 in2infty
= (in2_x
[0] | in2_x
[1] | in2_x
[2] | in2_x
[3] |
441 in2_y
[0] | in2_y
[1] | in2_y
[2] | in2_y
[3]);
443 in2infty
|= (in2_x
[4] | in2_x
[5] | in2_x
[6] | in2_x
[7] |
444 in2_y
[4] | in2_y
[5] | in2_y
[6] | in2_y
[7]);
446 in1infty
= is_zero(in1infty
);
447 in2infty
= is_zero(in2infty
);
449 ecp_nistz256_sqr_mont(Z1sqr
, in1_z
); /* Z1^2 */
451 ecp_nistz256_mul_mont(U2
, in2_x
, Z1sqr
); /* U2 = X2*Z1^2 */
452 ecp_nistz256_sub(H
, U2
, in1_x
); /* H = U2 - U1 */
454 ecp_nistz256_mul_mont(S2
, Z1sqr
, in1_z
); /* S2 = Z1^3 */
456 ecp_nistz256_mul_mont(res_z
, H
, in1_z
); /* Z3 = H*Z1*Z2 */
458 ecp_nistz256_mul_mont(S2
, S2
, in2_y
); /* S2 = Y2*Z1^3 */
459 ecp_nistz256_sub(R
, S2
, in1_y
); /* R = S2 - S1 */
461 ecp_nistz256_sqr_mont(Hsqr
, H
); /* H^2 */
462 ecp_nistz256_sqr_mont(Rsqr
, R
); /* R^2 */
463 ecp_nistz256_mul_mont(Hcub
, Hsqr
, H
); /* H^3 */
465 ecp_nistz256_mul_mont(U2
, in1_x
, Hsqr
); /* U1*H^2 */
466 ecp_nistz256_mul_by_2(Hsqr
, U2
); /* 2*U1*H^2 */
468 ecp_nistz256_sub(res_x
, Rsqr
, Hsqr
);
469 ecp_nistz256_sub(res_x
, res_x
, Hcub
);
470 ecp_nistz256_sub(H
, U2
, res_x
);
472 ecp_nistz256_mul_mont(S2
, in1_y
, Hcub
);
473 ecp_nistz256_mul_mont(H
, H
, R
);
474 ecp_nistz256_sub(res_y
, H
, S2
);
476 copy_conditional(res_x
, in2_x
, in1infty
);
477 copy_conditional(res_x
, in1_x
, in2infty
);
479 copy_conditional(res_y
, in2_y
, in1infty
);
480 copy_conditional(res_y
, in1_y
, in2infty
);
482 copy_conditional(res_z
, ONE
, in1infty
);
483 copy_conditional(res_z
, in1_z
, in2infty
);
485 memcpy(r
->X
, res_x
, sizeof(res_x
));
486 memcpy(r
->Y
, res_y
, sizeof(res_y
));
487 memcpy(r
->Z
, res_z
, sizeof(res_z
));
491 /* r = in^-1 mod p */
492 static void ecp_nistz256_mod_inverse(BN_ULONG r
[P256_LIMBS
],
493 const BN_ULONG in
[P256_LIMBS
])
496 * The poly is ffffffff 00000001 00000000 00000000 00000000 ffffffff
497 * ffffffff ffffffff We use FLT and used poly-2 as exponent
499 BN_ULONG p2
[P256_LIMBS
];
500 BN_ULONG p4
[P256_LIMBS
];
501 BN_ULONG p8
[P256_LIMBS
];
502 BN_ULONG p16
[P256_LIMBS
];
503 BN_ULONG p32
[P256_LIMBS
];
504 BN_ULONG res
[P256_LIMBS
];
507 ecp_nistz256_sqr_mont(res
, in
);
508 ecp_nistz256_mul_mont(p2
, res
, in
); /* 3*p */
510 ecp_nistz256_sqr_mont(res
, p2
);
511 ecp_nistz256_sqr_mont(res
, res
);
512 ecp_nistz256_mul_mont(p4
, res
, p2
); /* f*p */
514 ecp_nistz256_sqr_mont(res
, p4
);
515 ecp_nistz256_sqr_mont(res
, res
);
516 ecp_nistz256_sqr_mont(res
, res
);
517 ecp_nistz256_sqr_mont(res
, res
);
518 ecp_nistz256_mul_mont(p8
, res
, p4
); /* ff*p */
520 ecp_nistz256_sqr_mont(res
, p8
);
521 for (i
= 0; i
< 7; i
++)
522 ecp_nistz256_sqr_mont(res
, res
);
523 ecp_nistz256_mul_mont(p16
, res
, p8
); /* ffff*p */
525 ecp_nistz256_sqr_mont(res
, p16
);
526 for (i
= 0; i
< 15; i
++)
527 ecp_nistz256_sqr_mont(res
, res
);
528 ecp_nistz256_mul_mont(p32
, res
, p16
); /* ffffffff*p */
530 ecp_nistz256_sqr_mont(res
, p32
);
531 for (i
= 0; i
< 31; i
++)
532 ecp_nistz256_sqr_mont(res
, res
);
533 ecp_nistz256_mul_mont(res
, res
, in
);
535 for (i
= 0; i
< 32 * 4; i
++)
536 ecp_nistz256_sqr_mont(res
, res
);
537 ecp_nistz256_mul_mont(res
, res
, p32
);
539 for (i
= 0; i
< 32; i
++)
540 ecp_nistz256_sqr_mont(res
, res
);
541 ecp_nistz256_mul_mont(res
, res
, p32
);
543 for (i
= 0; i
< 16; i
++)
544 ecp_nistz256_sqr_mont(res
, res
);
545 ecp_nistz256_mul_mont(res
, res
, p16
);
547 for (i
= 0; i
< 8; i
++)
548 ecp_nistz256_sqr_mont(res
, res
);
549 ecp_nistz256_mul_mont(res
, res
, p8
);
551 ecp_nistz256_sqr_mont(res
, res
);
552 ecp_nistz256_sqr_mont(res
, res
);
553 ecp_nistz256_sqr_mont(res
, res
);
554 ecp_nistz256_sqr_mont(res
, res
);
555 ecp_nistz256_mul_mont(res
, res
, p4
);
557 ecp_nistz256_sqr_mont(res
, res
);
558 ecp_nistz256_sqr_mont(res
, res
);
559 ecp_nistz256_mul_mont(res
, res
, p2
);
561 ecp_nistz256_sqr_mont(res
, res
);
562 ecp_nistz256_sqr_mont(res
, res
);
563 ecp_nistz256_mul_mont(res
, res
, in
);
565 memcpy(r
, res
, sizeof(res
));
569 * ecp_nistz256_bignum_to_field_elem copies the contents of |in| to |out| and
570 * returns one if it fits. Otherwise it returns zero.
572 __owur
static int ecp_nistz256_bignum_to_field_elem(BN_ULONG out
[P256_LIMBS
],
575 return bn_copy_words(out
, in
, P256_LIMBS
);
578 /* r = sum(scalar[i]*point[i]) */
579 __owur
static int ecp_nistz256_windowed_mul(const EC_GROUP
*group
,
581 const BIGNUM
**scalar
,
582 const EC_POINT
**point
,
583 size_t num
, BN_CTX
*ctx
)
588 unsigned char (*p_str
)[33] = NULL
;
589 const unsigned int window_size
= 5;
590 const unsigned int mask
= (1 << (window_size
+ 1)) - 1;
592 P256_POINT
*temp
; /* place for 5 temporary points */
593 const BIGNUM
**scalars
= NULL
;
594 P256_POINT (*table
)[16] = NULL
;
595 void *table_storage
= NULL
;
597 if ((num
* 16 + 6) > OPENSSL_MALLOC_MAX_NELEMS(P256_POINT
)
599 OPENSSL_malloc((num
* 16 + 5) * sizeof(P256_POINT
) + 64)) == NULL
601 OPENSSL_malloc(num
* 33 * sizeof(unsigned char))) == NULL
602 || (scalars
= OPENSSL_malloc(num
* sizeof(BIGNUM
*))) == NULL
) {
603 ECerr(EC_F_ECP_NISTZ256_WINDOWED_MUL
, ERR_R_MALLOC_FAILURE
);
607 table
= (void *)ALIGNPTR(table_storage
, 64);
608 temp
= (P256_POINT
*)(table
+ num
);
610 for (i
= 0; i
< num
; i
++) {
611 P256_POINT
*row
= table
[i
];
613 /* This is an unusual input, we don't guarantee constant-timeness. */
614 if ((BN_num_bits(scalar
[i
]) > 256) || BN_is_negative(scalar
[i
])) {
617 if ((mod
= BN_CTX_get(ctx
)) == NULL
)
619 if (!BN_nnmod(mod
, scalar
[i
], group
->order
, ctx
)) {
620 ECerr(EC_F_ECP_NISTZ256_WINDOWED_MUL
, ERR_R_BN_LIB
);
625 scalars
[i
] = scalar
[i
];
627 for (j
= 0; j
< bn_get_top(scalars
[i
]) * BN_BYTES
; j
+= BN_BYTES
) {
628 BN_ULONG d
= bn_get_words(scalars
[i
])[j
/ BN_BYTES
];
630 p_str
[i
][j
+ 0] = (unsigned char)d
;
631 p_str
[i
][j
+ 1] = (unsigned char)(d
>> 8);
632 p_str
[i
][j
+ 2] = (unsigned char)(d
>> 16);
633 p_str
[i
][j
+ 3] = (unsigned char)(d
>>= 24);
636 p_str
[i
][j
+ 4] = (unsigned char)d
;
637 p_str
[i
][j
+ 5] = (unsigned char)(d
>> 8);
638 p_str
[i
][j
+ 6] = (unsigned char)(d
>> 16);
639 p_str
[i
][j
+ 7] = (unsigned char)(d
>> 24);
645 if (!ecp_nistz256_bignum_to_field_elem(temp
[0].X
, point
[i
]->X
)
646 || !ecp_nistz256_bignum_to_field_elem(temp
[0].Y
, point
[i
]->Y
)
647 || !ecp_nistz256_bignum_to_field_elem(temp
[0].Z
, point
[i
]->Z
)) {
648 ECerr(EC_F_ECP_NISTZ256_WINDOWED_MUL
,
649 EC_R_COORDINATES_OUT_OF_RANGE
);
654 * row[0] is implicitly (0,0,0) (the point at infinity), therefore it
655 * is not stored. All other values are actually stored with an offset
659 ecp_nistz256_scatter_w5 (row
, &temp
[0], 1);
660 ecp_nistz256_point_double(&temp
[1], &temp
[0]); /*1+1=2 */
661 ecp_nistz256_scatter_w5 (row
, &temp
[1], 2);
662 ecp_nistz256_point_add (&temp
[2], &temp
[1], &temp
[0]); /*2+1=3 */
663 ecp_nistz256_scatter_w5 (row
, &temp
[2], 3);
664 ecp_nistz256_point_double(&temp
[1], &temp
[1]); /*2*2=4 */
665 ecp_nistz256_scatter_w5 (row
, &temp
[1], 4);
666 ecp_nistz256_point_double(&temp
[2], &temp
[2]); /*2*3=6 */
667 ecp_nistz256_scatter_w5 (row
, &temp
[2], 6);
668 ecp_nistz256_point_add (&temp
[3], &temp
[1], &temp
[0]); /*4+1=5 */
669 ecp_nistz256_scatter_w5 (row
, &temp
[3], 5);
670 ecp_nistz256_point_add (&temp
[4], &temp
[2], &temp
[0]); /*6+1=7 */
671 ecp_nistz256_scatter_w5 (row
, &temp
[4], 7);
672 ecp_nistz256_point_double(&temp
[1], &temp
[1]); /*2*4=8 */
673 ecp_nistz256_scatter_w5 (row
, &temp
[1], 8);
674 ecp_nistz256_point_double(&temp
[2], &temp
[2]); /*2*6=12 */
675 ecp_nistz256_scatter_w5 (row
, &temp
[2], 12);
676 ecp_nistz256_point_double(&temp
[3], &temp
[3]); /*2*5=10 */
677 ecp_nistz256_scatter_w5 (row
, &temp
[3], 10);
678 ecp_nistz256_point_double(&temp
[4], &temp
[4]); /*2*7=14 */
679 ecp_nistz256_scatter_w5 (row
, &temp
[4], 14);
680 ecp_nistz256_point_add (&temp
[2], &temp
[2], &temp
[0]); /*12+1=13*/
681 ecp_nistz256_scatter_w5 (row
, &temp
[2], 13);
682 ecp_nistz256_point_add (&temp
[3], &temp
[3], &temp
[0]); /*10+1=11*/
683 ecp_nistz256_scatter_w5 (row
, &temp
[3], 11);
684 ecp_nistz256_point_add (&temp
[4], &temp
[4], &temp
[0]); /*14+1=15*/
685 ecp_nistz256_scatter_w5 (row
, &temp
[4], 15);
686 ecp_nistz256_point_add (&temp
[2], &temp
[1], &temp
[0]); /*8+1=9 */
687 ecp_nistz256_scatter_w5 (row
, &temp
[2], 9);
688 ecp_nistz256_point_double(&temp
[1], &temp
[1]); /*2*8=16 */
689 ecp_nistz256_scatter_w5 (row
, &temp
[1], 16);
694 wvalue
= p_str
[0][(idx
- 1) / 8];
695 wvalue
= (wvalue
>> ((idx
- 1) % 8)) & mask
;
698 * We gather to temp[0], because we know it's position relative
701 ecp_nistz256_gather_w5(&temp
[0], table
[0], _booth_recode_w5(wvalue
) >> 1);
702 memcpy(r
, &temp
[0], sizeof(temp
[0]));
705 for (i
= (idx
== 255 ? 1 : 0); i
< num
; i
++) {
706 unsigned int off
= (idx
- 1) / 8;
708 wvalue
= p_str
[i
][off
] | p_str
[i
][off
+ 1] << 8;
709 wvalue
= (wvalue
>> ((idx
- 1) % 8)) & mask
;
711 wvalue
= _booth_recode_w5(wvalue
);
713 ecp_nistz256_gather_w5(&temp
[0], table
[i
], wvalue
>> 1);
715 ecp_nistz256_neg(temp
[1].Y
, temp
[0].Y
);
716 copy_conditional(temp
[0].Y
, temp
[1].Y
, (wvalue
& 1));
718 ecp_nistz256_point_add(r
, r
, &temp
[0]);
723 ecp_nistz256_point_double(r
, r
);
724 ecp_nistz256_point_double(r
, r
);
725 ecp_nistz256_point_double(r
, r
);
726 ecp_nistz256_point_double(r
, r
);
727 ecp_nistz256_point_double(r
, r
);
731 for (i
= 0; i
< num
; i
++) {
732 wvalue
= p_str
[i
][0];
733 wvalue
= (wvalue
<< 1) & mask
;
735 wvalue
= _booth_recode_w5(wvalue
);
737 ecp_nistz256_gather_w5(&temp
[0], table
[i
], wvalue
>> 1);
739 ecp_nistz256_neg(temp
[1].Y
, temp
[0].Y
);
740 copy_conditional(temp
[0].Y
, temp
[1].Y
, wvalue
& 1);
742 ecp_nistz256_point_add(r
, r
, &temp
[0]);
747 OPENSSL_free(table_storage
);
749 OPENSSL_free(scalars
);
753 /* Coordinates of G, for which we have precomputed tables */
754 static const BN_ULONG def_xG
[P256_LIMBS
] = {
755 TOBN(0x79e730d4, 0x18a9143c), TOBN(0x75ba95fc, 0x5fedb601),
756 TOBN(0x79fb732b, 0x77622510), TOBN(0x18905f76, 0xa53755c6)
759 static const BN_ULONG def_yG
[P256_LIMBS
] = {
760 TOBN(0xddf25357, 0xce95560a), TOBN(0x8b4ab8e4, 0xba19e45c),
761 TOBN(0xd2e88688, 0xdd21f325), TOBN(0x8571ff18, 0x25885d85)
765 * ecp_nistz256_is_affine_G returns one if |generator| is the standard, P-256
768 static int ecp_nistz256_is_affine_G(const EC_POINT
*generator
)
770 return (bn_get_top(generator
->X
) == P256_LIMBS
) &&
771 (bn_get_top(generator
->Y
) == P256_LIMBS
) &&
772 is_equal(bn_get_words(generator
->X
), def_xG
) &&
773 is_equal(bn_get_words(generator
->Y
), def_yG
) &&
774 is_one(generator
->Z
);
777 __owur
static int ecp_nistz256_mult_precompute(EC_GROUP
*group
, BN_CTX
*ctx
)
780 * We precompute a table for a Booth encoded exponent (wNAF) based
781 * computation. Each table holds 64 values for safe access, with an
782 * implicit value of infinity at index zero. We use window of size 7, and
783 * therefore require ceil(256/7) = 37 tables.
786 EC_POINT
*P
= NULL
, *T
= NULL
;
787 const EC_POINT
*generator
;
788 NISTZ256_PRE_COMP
*pre_comp
;
789 BN_CTX
*new_ctx
= NULL
;
790 int i
, j
, k
, ret
= 0;
793 PRECOMP256_ROW
*preComputedTable
= NULL
;
794 unsigned char *precomp_storage
= NULL
;
796 /* if there is an old NISTZ256_PRE_COMP object, throw it away */
797 EC_pre_comp_free(group
);
798 generator
= EC_GROUP_get0_generator(group
);
799 if (generator
== NULL
) {
800 ECerr(EC_F_ECP_NISTZ256_MULT_PRECOMPUTE
, EC_R_UNDEFINED_GENERATOR
);
804 if (ecp_nistz256_is_affine_G(generator
)) {
806 * No need to calculate tables for the standard generator because we
807 * have them statically.
812 if ((pre_comp
= ecp_nistz256_pre_comp_new(group
)) == NULL
)
816 ctx
= new_ctx
= BN_CTX_new_ex(group
->libctx
);
823 order
= EC_GROUP_get0_order(group
);
827 if (BN_is_zero(order
)) {
828 ECerr(EC_F_ECP_NISTZ256_MULT_PRECOMPUTE
, EC_R_UNKNOWN_ORDER
);
834 if ((precomp_storage
=
835 OPENSSL_malloc(37 * 64 * sizeof(P256_POINT_AFFINE
) + 64)) == NULL
) {
836 ECerr(EC_F_ECP_NISTZ256_MULT_PRECOMPUTE
, ERR_R_MALLOC_FAILURE
);
840 preComputedTable
= (void *)ALIGNPTR(precomp_storage
, 64);
842 P
= EC_POINT_new(group
);
843 T
= EC_POINT_new(group
);
844 if (P
== NULL
|| T
== NULL
)
848 * The zero entry is implicitly infinity, and we skip it, storing other
849 * values with -1 offset.
851 if (!EC_POINT_copy(T
, generator
))
854 for (k
= 0; k
< 64; k
++) {
855 if (!EC_POINT_copy(P
, T
))
857 for (j
= 0; j
< 37; j
++) {
858 P256_POINT_AFFINE temp
;
860 * It would be faster to use EC_POINTs_make_affine and
861 * make multiple points affine at the same time.
863 if (!EC_POINT_make_affine(group
, P
, ctx
))
865 if (!ecp_nistz256_bignum_to_field_elem(temp
.X
, P
->X
) ||
866 !ecp_nistz256_bignum_to_field_elem(temp
.Y
, P
->Y
)) {
867 ECerr(EC_F_ECP_NISTZ256_MULT_PRECOMPUTE
,
868 EC_R_COORDINATES_OUT_OF_RANGE
);
871 ecp_nistz256_scatter_w7(preComputedTable
[j
], &temp
, k
);
872 for (i
= 0; i
< 7; i
++) {
873 if (!EC_POINT_dbl(group
, P
, P
, ctx
))
877 if (!EC_POINT_add(group
, T
, T
, generator
, ctx
))
881 pre_comp
->group
= group
;
883 pre_comp
->precomp
= preComputedTable
;
884 pre_comp
->precomp_storage
= precomp_storage
;
885 precomp_storage
= NULL
;
886 SETPRECOMP(group
, nistz256
, pre_comp
);
892 BN_CTX_free(new_ctx
);
894 EC_nistz256_pre_comp_free(pre_comp
);
895 OPENSSL_free(precomp_storage
);
902 * Note that by default ECP_NISTZ256_AVX2 is undefined. While it's great
903 * code processing 4 points in parallel, corresponding serial operation
904 * is several times slower, because it uses 29x29=58-bit multiplication
905 * as opposite to 64x64=128-bit in integer-only scalar case. As result
906 * it doesn't provide *significant* performance improvement. Note that
907 * just defining ECP_NISTZ256_AVX2 is not sufficient to make it work,
908 * you'd need to compile even asm/ecp_nistz256-avx.pl module.
910 #if defined(ECP_NISTZ256_AVX2)
911 # if !(defined(__x86_64) || defined(__x86_64__) || \
912 defined(_M_AMD64) || defined(_M_X64)) || \
913 !(defined(__GNUC__) || defined(_MSC_VER)) /* this is for ALIGN32 */
914 # undef ECP_NISTZ256_AVX2
916 /* Constant time access, loading four values, from four consecutive tables */
917 void ecp_nistz256_avx2_multi_gather_w7(void *result
, const void *in
,
918 int index0
, int index1
, int index2
,
920 void ecp_nistz256_avx2_transpose_convert(void *RESULTx4
, const void *in
);
921 void ecp_nistz256_avx2_convert_transpose_back(void *result
, const void *Ax4
);
922 void ecp_nistz256_avx2_point_add_affine_x4(void *RESULTx4
, const void *Ax4
,
924 void ecp_nistz256_avx2_point_add_affines_x4(void *RESULTx4
, const void *Ax4
,
926 void ecp_nistz256_avx2_to_mont(void *RESULTx4
, const void *Ax4
);
927 void ecp_nistz256_avx2_from_mont(void *RESULTx4
, const void *Ax4
);
928 void ecp_nistz256_avx2_set1(void *RESULTx4
);
929 int ecp_nistz_avx2_eligible(void);
931 static void booth_recode_w7(unsigned char *sign
,
932 unsigned char *digit
, unsigned char in
)
936 s
= ~((in
>> 7) - 1);
937 d
= (1 << 8) - in
- 1;
938 d
= (d
& s
) | (in
& ~s
);
939 d
= (d
>> 1) + (d
& 1);
946 * ecp_nistz256_avx2_mul_g performs multiplication by G, using only the
947 * precomputed table. It does 4 affine point additions in parallel,
948 * significantly speeding up point multiplication for a fixed value.
950 static void ecp_nistz256_avx2_mul_g(P256_POINT
*r
,
951 unsigned char p_str
[33],
952 const P256_POINT_AFFINE(*preComputedTable
)[64])
954 const unsigned int window_size
= 7;
955 const unsigned int mask
= (1 << (window_size
+ 1)) - 1;
957 /* Using 4 windows at a time */
958 unsigned char sign0
, digit0
;
959 unsigned char sign1
, digit1
;
960 unsigned char sign2
, digit2
;
961 unsigned char sign3
, digit3
;
962 unsigned int idx
= 0;
963 BN_ULONG tmp
[P256_LIMBS
];
966 ALIGN32 BN_ULONG aX4
[4 * 9 * 3] = { 0 };
967 ALIGN32 BN_ULONG bX4
[4 * 9 * 2] = { 0 };
968 ALIGN32 P256_POINT_AFFINE point_arr
[4];
969 ALIGN32 P256_POINT res_point_arr
[4];
971 /* Initial four windows */
972 wvalue
= *((u16
*) & p_str
[0]);
973 wvalue
= (wvalue
<< 1) & mask
;
975 booth_recode_w7(&sign0
, &digit0
, wvalue
);
976 wvalue
= *((u16
*) & p_str
[(idx
- 1) / 8]);
977 wvalue
= (wvalue
>> ((idx
- 1) % 8)) & mask
;
979 booth_recode_w7(&sign1
, &digit1
, wvalue
);
980 wvalue
= *((u16
*) & p_str
[(idx
- 1) / 8]);
981 wvalue
= (wvalue
>> ((idx
- 1) % 8)) & mask
;
983 booth_recode_w7(&sign2
, &digit2
, wvalue
);
984 wvalue
= *((u16
*) & p_str
[(idx
- 1) / 8]);
985 wvalue
= (wvalue
>> ((idx
- 1) % 8)) & mask
;
987 booth_recode_w7(&sign3
, &digit3
, wvalue
);
989 ecp_nistz256_avx2_multi_gather_w7(point_arr
, preComputedTable
[0],
990 digit0
, digit1
, digit2
, digit3
);
992 ecp_nistz256_neg(tmp
, point_arr
[0].Y
);
993 copy_conditional(point_arr
[0].Y
, tmp
, sign0
);
994 ecp_nistz256_neg(tmp
, point_arr
[1].Y
);
995 copy_conditional(point_arr
[1].Y
, tmp
, sign1
);
996 ecp_nistz256_neg(tmp
, point_arr
[2].Y
);
997 copy_conditional(point_arr
[2].Y
, tmp
, sign2
);
998 ecp_nistz256_neg(tmp
, point_arr
[3].Y
);
999 copy_conditional(point_arr
[3].Y
, tmp
, sign3
);
1001 ecp_nistz256_avx2_transpose_convert(aX4
, point_arr
);
1002 ecp_nistz256_avx2_to_mont(aX4
, aX4
);
1003 ecp_nistz256_avx2_to_mont(&aX4
[4 * 9], &aX4
[4 * 9]);
1004 ecp_nistz256_avx2_set1(&aX4
[4 * 9 * 2]);
1006 wvalue
= *((u16
*) & p_str
[(idx
- 1) / 8]);
1007 wvalue
= (wvalue
>> ((idx
- 1) % 8)) & mask
;
1009 booth_recode_w7(&sign0
, &digit0
, wvalue
);
1010 wvalue
= *((u16
*) & p_str
[(idx
- 1) / 8]);
1011 wvalue
= (wvalue
>> ((idx
- 1) % 8)) & mask
;
1013 booth_recode_w7(&sign1
, &digit1
, wvalue
);
1014 wvalue
= *((u16
*) & p_str
[(idx
- 1) / 8]);
1015 wvalue
= (wvalue
>> ((idx
- 1) % 8)) & mask
;
1017 booth_recode_w7(&sign2
, &digit2
, wvalue
);
1018 wvalue
= *((u16
*) & p_str
[(idx
- 1) / 8]);
1019 wvalue
= (wvalue
>> ((idx
- 1) % 8)) & mask
;
1021 booth_recode_w7(&sign3
, &digit3
, wvalue
);
1023 ecp_nistz256_avx2_multi_gather_w7(point_arr
, preComputedTable
[4 * 1],
1024 digit0
, digit1
, digit2
, digit3
);
1026 ecp_nistz256_neg(tmp
, point_arr
[0].Y
);
1027 copy_conditional(point_arr
[0].Y
, tmp
, sign0
);
1028 ecp_nistz256_neg(tmp
, point_arr
[1].Y
);
1029 copy_conditional(point_arr
[1].Y
, tmp
, sign1
);
1030 ecp_nistz256_neg(tmp
, point_arr
[2].Y
);
1031 copy_conditional(point_arr
[2].Y
, tmp
, sign2
);
1032 ecp_nistz256_neg(tmp
, point_arr
[3].Y
);
1033 copy_conditional(point_arr
[3].Y
, tmp
, sign3
);
1035 ecp_nistz256_avx2_transpose_convert(bX4
, point_arr
);
1036 ecp_nistz256_avx2_to_mont(bX4
, bX4
);
1037 ecp_nistz256_avx2_to_mont(&bX4
[4 * 9], &bX4
[4 * 9]);
1038 /* Optimized when both inputs are affine */
1039 ecp_nistz256_avx2_point_add_affines_x4(aX4
, aX4
, bX4
);
1041 for (i
= 2; i
< 9; i
++) {
1042 wvalue
= *((u16
*) & p_str
[(idx
- 1) / 8]);
1043 wvalue
= (wvalue
>> ((idx
- 1) % 8)) & mask
;
1045 booth_recode_w7(&sign0
, &digit0
, wvalue
);
1046 wvalue
= *((u16
*) & p_str
[(idx
- 1) / 8]);
1047 wvalue
= (wvalue
>> ((idx
- 1) % 8)) & mask
;
1049 booth_recode_w7(&sign1
, &digit1
, wvalue
);
1050 wvalue
= *((u16
*) & p_str
[(idx
- 1) / 8]);
1051 wvalue
= (wvalue
>> ((idx
- 1) % 8)) & mask
;
1053 booth_recode_w7(&sign2
, &digit2
, wvalue
);
1054 wvalue
= *((u16
*) & p_str
[(idx
- 1) / 8]);
1055 wvalue
= (wvalue
>> ((idx
- 1) % 8)) & mask
;
1057 booth_recode_w7(&sign3
, &digit3
, wvalue
);
1059 ecp_nistz256_avx2_multi_gather_w7(point_arr
,
1060 preComputedTable
[4 * i
],
1061 digit0
, digit1
, digit2
, digit3
);
1063 ecp_nistz256_neg(tmp
, point_arr
[0].Y
);
1064 copy_conditional(point_arr
[0].Y
, tmp
, sign0
);
1065 ecp_nistz256_neg(tmp
, point_arr
[1].Y
);
1066 copy_conditional(point_arr
[1].Y
, tmp
, sign1
);
1067 ecp_nistz256_neg(tmp
, point_arr
[2].Y
);
1068 copy_conditional(point_arr
[2].Y
, tmp
, sign2
);
1069 ecp_nistz256_neg(tmp
, point_arr
[3].Y
);
1070 copy_conditional(point_arr
[3].Y
, tmp
, sign3
);
1072 ecp_nistz256_avx2_transpose_convert(bX4
, point_arr
);
1073 ecp_nistz256_avx2_to_mont(bX4
, bX4
);
1074 ecp_nistz256_avx2_to_mont(&bX4
[4 * 9], &bX4
[4 * 9]);
1076 ecp_nistz256_avx2_point_add_affine_x4(aX4
, aX4
, bX4
);
1079 ecp_nistz256_avx2_from_mont(&aX4
[4 * 9 * 0], &aX4
[4 * 9 * 0]);
1080 ecp_nistz256_avx2_from_mont(&aX4
[4 * 9 * 1], &aX4
[4 * 9 * 1]);
1081 ecp_nistz256_avx2_from_mont(&aX4
[4 * 9 * 2], &aX4
[4 * 9 * 2]);
1083 ecp_nistz256_avx2_convert_transpose_back(res_point_arr
, aX4
);
1084 /* Last window is performed serially */
1085 wvalue
= *((u16
*) & p_str
[(idx
- 1) / 8]);
1086 wvalue
= (wvalue
>> ((idx
- 1) % 8)) & mask
;
1087 booth_recode_w7(&sign0
, &digit0
, wvalue
);
1088 ecp_nistz256_gather_w7((P256_POINT_AFFINE
*)r
,
1089 preComputedTable
[36], digit0
);
1090 ecp_nistz256_neg(tmp
, r
->Y
);
1091 copy_conditional(r
->Y
, tmp
, sign0
);
1092 memcpy(r
->Z
, ONE
, sizeof(ONE
));
1093 /* Sum the four windows */
1094 ecp_nistz256_point_add(r
, r
, &res_point_arr
[0]);
1095 ecp_nistz256_point_add(r
, r
, &res_point_arr
[1]);
1096 ecp_nistz256_point_add(r
, r
, &res_point_arr
[2]);
1097 ecp_nistz256_point_add(r
, r
, &res_point_arr
[3]);
1102 __owur
static int ecp_nistz256_set_from_affine(EC_POINT
*out
, const EC_GROUP
*group
,
1103 const P256_POINT_AFFINE
*in
,
1108 if ((ret
= bn_set_words(out
->X
, in
->X
, P256_LIMBS
))
1109 && (ret
= bn_set_words(out
->Y
, in
->Y
, P256_LIMBS
))
1110 && (ret
= bn_set_words(out
->Z
, ONE
, P256_LIMBS
)))
1116 /* r = scalar*G + sum(scalars[i]*points[i]) */
1117 __owur
static int ecp_nistz256_points_mul(const EC_GROUP
*group
,
1119 const BIGNUM
*scalar
,
1121 const EC_POINT
*points
[],
1122 const BIGNUM
*scalars
[], BN_CTX
*ctx
)
1124 int i
= 0, ret
= 0, no_precomp_for_generator
= 0, p_is_infinity
= 0;
1125 unsigned char p_str
[33] = { 0 };
1126 const PRECOMP256_ROW
*preComputedTable
= NULL
;
1127 const NISTZ256_PRE_COMP
*pre_comp
= NULL
;
1128 const EC_POINT
*generator
= NULL
;
1129 const BIGNUM
**new_scalars
= NULL
;
1130 const EC_POINT
**new_points
= NULL
;
1131 unsigned int idx
= 0;
1132 const unsigned int window_size
= 7;
1133 const unsigned int mask
= (1 << (window_size
+ 1)) - 1;
1134 unsigned int wvalue
;
1137 P256_POINT_AFFINE a
;
1141 if ((num
+ 1) == 0 || (num
+ 1) > OPENSSL_MALLOC_MAX_NELEMS(void *)) {
1142 ECerr(EC_F_ECP_NISTZ256_POINTS_MUL
, ERR_R_MALLOC_FAILURE
);
1149 generator
= EC_GROUP_get0_generator(group
);
1150 if (generator
== NULL
) {
1151 ECerr(EC_F_ECP_NISTZ256_POINTS_MUL
, EC_R_UNDEFINED_GENERATOR
);
1155 /* look if we can use precomputed multiples of generator */
1156 pre_comp
= group
->pre_comp
.nistz256
;
1160 * If there is a precomputed table for the generator, check that
1161 * it was generated with the same generator.
1163 EC_POINT
*pre_comp_generator
= EC_POINT_new(group
);
1164 if (pre_comp_generator
== NULL
)
1167 ecp_nistz256_gather_w7(&p
.a
, pre_comp
->precomp
[0], 1);
1168 if (!ecp_nistz256_set_from_affine(pre_comp_generator
,
1169 group
, &p
.a
, ctx
)) {
1170 EC_POINT_free(pre_comp_generator
);
1174 if (0 == EC_POINT_cmp(group
, generator
, pre_comp_generator
, ctx
))
1175 preComputedTable
= (const PRECOMP256_ROW
*)pre_comp
->precomp
;
1177 EC_POINT_free(pre_comp_generator
);
1180 if (preComputedTable
== NULL
&& ecp_nistz256_is_affine_G(generator
)) {
1182 * If there is no precomputed data, but the generator is the
1183 * default, a hardcoded table of precomputed data is used. This
1184 * is because applications, such as Apache, do not use
1185 * EC_KEY_precompute_mult.
1187 preComputedTable
= ecp_nistz256_precomputed
;
1190 if (preComputedTable
) {
1191 if ((BN_num_bits(scalar
) > 256)
1192 || BN_is_negative(scalar
)) {
1193 if ((tmp_scalar
= BN_CTX_get(ctx
)) == NULL
)
1196 if (!BN_nnmod(tmp_scalar
, scalar
, group
->order
, ctx
)) {
1197 ECerr(EC_F_ECP_NISTZ256_POINTS_MUL
, ERR_R_BN_LIB
);
1200 scalar
= tmp_scalar
;
1203 for (i
= 0; i
< bn_get_top(scalar
) * BN_BYTES
; i
+= BN_BYTES
) {
1204 BN_ULONG d
= bn_get_words(scalar
)[i
/ BN_BYTES
];
1206 p_str
[i
+ 0] = (unsigned char)d
;
1207 p_str
[i
+ 1] = (unsigned char)(d
>> 8);
1208 p_str
[i
+ 2] = (unsigned char)(d
>> 16);
1209 p_str
[i
+ 3] = (unsigned char)(d
>>= 24);
1210 if (BN_BYTES
== 8) {
1212 p_str
[i
+ 4] = (unsigned char)d
;
1213 p_str
[i
+ 5] = (unsigned char)(d
>> 8);
1214 p_str
[i
+ 6] = (unsigned char)(d
>> 16);
1215 p_str
[i
+ 7] = (unsigned char)(d
>> 24);
1222 #if defined(ECP_NISTZ256_AVX2)
1223 if (ecp_nistz_avx2_eligible()) {
1224 ecp_nistz256_avx2_mul_g(&p
.p
, p_str
, preComputedTable
);
1231 wvalue
= (p_str
[0] << 1) & mask
;
1234 wvalue
= _booth_recode_w7(wvalue
);
1236 ecp_nistz256_gather_w7(&p
.a
, preComputedTable
[0],
1239 ecp_nistz256_neg(p
.p
.Z
, p
.p
.Y
);
1240 copy_conditional(p
.p
.Y
, p
.p
.Z
, wvalue
& 1);
1243 * Since affine infinity is encoded as (0,0) and
1244 * Jacobian ias (,,0), we need to harmonize them
1245 * by assigning "one" or zero to Z.
1247 infty
= (p
.p
.X
[0] | p
.p
.X
[1] | p
.p
.X
[2] | p
.p
.X
[3] |
1248 p
.p
.Y
[0] | p
.p
.Y
[1] | p
.p
.Y
[2] | p
.p
.Y
[3]);
1249 if (P256_LIMBS
== 8)
1250 infty
|= (p
.p
.X
[4] | p
.p
.X
[5] | p
.p
.X
[6] | p
.p
.X
[7] |
1251 p
.p
.Y
[4] | p
.p
.Y
[5] | p
.p
.Y
[6] | p
.p
.Y
[7]);
1253 infty
= 0 - is_zero(infty
);
1256 p
.p
.Z
[0] = ONE
[0] & infty
;
1257 p
.p
.Z
[1] = ONE
[1] & infty
;
1258 p
.p
.Z
[2] = ONE
[2] & infty
;
1259 p
.p
.Z
[3] = ONE
[3] & infty
;
1260 if (P256_LIMBS
== 8) {
1261 p
.p
.Z
[4] = ONE
[4] & infty
;
1262 p
.p
.Z
[5] = ONE
[5] & infty
;
1263 p
.p
.Z
[6] = ONE
[6] & infty
;
1264 p
.p
.Z
[7] = ONE
[7] & infty
;
1267 for (i
= 1; i
< 37; i
++) {
1268 unsigned int off
= (idx
- 1) / 8;
1269 wvalue
= p_str
[off
] | p_str
[off
+ 1] << 8;
1270 wvalue
= (wvalue
>> ((idx
- 1) % 8)) & mask
;
1273 wvalue
= _booth_recode_w7(wvalue
);
1275 ecp_nistz256_gather_w7(&t
.a
,
1276 preComputedTable
[i
], wvalue
>> 1);
1278 ecp_nistz256_neg(t
.p
.Z
, t
.a
.Y
);
1279 copy_conditional(t
.a
.Y
, t
.p
.Z
, wvalue
& 1);
1281 ecp_nistz256_point_add_affine(&p
.p
, &p
.p
, &t
.a
);
1286 no_precomp_for_generator
= 1;
1291 if (no_precomp_for_generator
) {
1293 * Without a precomputed table for the generator, it has to be
1294 * handled like a normal point.
1296 new_scalars
= OPENSSL_malloc((num
+ 1) * sizeof(BIGNUM
*));
1297 if (new_scalars
== NULL
) {
1298 ECerr(EC_F_ECP_NISTZ256_POINTS_MUL
, ERR_R_MALLOC_FAILURE
);
1302 new_points
= OPENSSL_malloc((num
+ 1) * sizeof(EC_POINT
*));
1303 if (new_points
== NULL
) {
1304 ECerr(EC_F_ECP_NISTZ256_POINTS_MUL
, ERR_R_MALLOC_FAILURE
);
1308 memcpy(new_scalars
, scalars
, num
* sizeof(BIGNUM
*));
1309 new_scalars
[num
] = scalar
;
1310 memcpy(new_points
, points
, num
* sizeof(EC_POINT
*));
1311 new_points
[num
] = generator
;
1313 scalars
= new_scalars
;
1314 points
= new_points
;
1319 P256_POINT
*out
= &t
.p
;
1323 if (!ecp_nistz256_windowed_mul(group
, out
, scalars
, points
, num
, ctx
))
1327 ecp_nistz256_point_add(&p
.p
, &p
.p
, out
);
1330 /* Not constant-time, but we're only operating on the public output. */
1331 if (!bn_set_words(r
->X
, p
.p
.X
, P256_LIMBS
) ||
1332 !bn_set_words(r
->Y
, p
.p
.Y
, P256_LIMBS
) ||
1333 !bn_set_words(r
->Z
, p
.p
.Z
, P256_LIMBS
)) {
1336 r
->Z_is_one
= is_one(r
->Z
) & 1;
1342 OPENSSL_free(new_points
);
1343 OPENSSL_free(new_scalars
);
1347 __owur
static int ecp_nistz256_get_affine(const EC_GROUP
*group
,
1348 const EC_POINT
*point
,
1349 BIGNUM
*x
, BIGNUM
*y
, BN_CTX
*ctx
)
1351 BN_ULONG z_inv2
[P256_LIMBS
];
1352 BN_ULONG z_inv3
[P256_LIMBS
];
1353 BN_ULONG x_aff
[P256_LIMBS
];
1354 BN_ULONG y_aff
[P256_LIMBS
];
1355 BN_ULONG point_x
[P256_LIMBS
], point_y
[P256_LIMBS
], point_z
[P256_LIMBS
];
1356 BN_ULONG x_ret
[P256_LIMBS
], y_ret
[P256_LIMBS
];
1358 if (EC_POINT_is_at_infinity(group
, point
)) {
1359 ECerr(EC_F_ECP_NISTZ256_GET_AFFINE
, EC_R_POINT_AT_INFINITY
);
1363 if (!ecp_nistz256_bignum_to_field_elem(point_x
, point
->X
) ||
1364 !ecp_nistz256_bignum_to_field_elem(point_y
, point
->Y
) ||
1365 !ecp_nistz256_bignum_to_field_elem(point_z
, point
->Z
)) {
1366 ECerr(EC_F_ECP_NISTZ256_GET_AFFINE
, EC_R_COORDINATES_OUT_OF_RANGE
);
1370 ecp_nistz256_mod_inverse(z_inv3
, point_z
);
1371 ecp_nistz256_sqr_mont(z_inv2
, z_inv3
);
1372 ecp_nistz256_mul_mont(x_aff
, z_inv2
, point_x
);
1375 ecp_nistz256_from_mont(x_ret
, x_aff
);
1376 if (!bn_set_words(x
, x_ret
, P256_LIMBS
))
1381 ecp_nistz256_mul_mont(z_inv3
, z_inv3
, z_inv2
);
1382 ecp_nistz256_mul_mont(y_aff
, z_inv3
, point_y
);
1383 ecp_nistz256_from_mont(y_ret
, y_aff
);
1384 if (!bn_set_words(y
, y_ret
, P256_LIMBS
))
1391 static NISTZ256_PRE_COMP
*ecp_nistz256_pre_comp_new(const EC_GROUP
*group
)
1393 NISTZ256_PRE_COMP
*ret
= NULL
;
1398 ret
= OPENSSL_zalloc(sizeof(*ret
));
1401 ECerr(EC_F_ECP_NISTZ256_PRE_COMP_NEW
, ERR_R_MALLOC_FAILURE
);
1406 ret
->w
= 6; /* default */
1407 ret
->references
= 1;
1409 ret
->lock
= CRYPTO_THREAD_lock_new();
1410 if (ret
->lock
== NULL
) {
1411 ECerr(EC_F_ECP_NISTZ256_PRE_COMP_NEW
, ERR_R_MALLOC_FAILURE
);
1418 NISTZ256_PRE_COMP
*EC_nistz256_pre_comp_dup(NISTZ256_PRE_COMP
*p
)
1422 CRYPTO_UP_REF(&p
->references
, &i
, p
->lock
);
1426 void EC_nistz256_pre_comp_free(NISTZ256_PRE_COMP
*pre
)
1433 CRYPTO_DOWN_REF(&pre
->references
, &i
, pre
->lock
);
1434 REF_PRINT_COUNT("EC_nistz256", pre
);
1437 REF_ASSERT_ISNT(i
< 0);
1439 OPENSSL_free(pre
->precomp_storage
);
1440 CRYPTO_THREAD_lock_free(pre
->lock
);
1445 static int ecp_nistz256_window_have_precompute_mult(const EC_GROUP
*group
)
1447 /* There is a hard-coded table for the default generator. */
1448 const EC_POINT
*generator
= EC_GROUP_get0_generator(group
);
1450 if (generator
!= NULL
&& ecp_nistz256_is_affine_G(generator
)) {
1451 /* There is a hard-coded table for the default generator. */
1455 return HAVEPRECOMP(group
, nistz256
);
1458 #if defined(__x86_64) || defined(__x86_64__) || \
1459 defined(_M_AMD64) || defined(_M_X64) || \
1460 defined(__powerpc64__) || defined(_ARCH_PP64) || \
1461 defined(__aarch64__)
1463 * Montgomery mul modulo Order(P): res = a*b*2^-256 mod Order(P)
1465 void ecp_nistz256_ord_mul_mont(BN_ULONG res
[P256_LIMBS
],
1466 const BN_ULONG a
[P256_LIMBS
],
1467 const BN_ULONG b
[P256_LIMBS
]);
1468 void ecp_nistz256_ord_sqr_mont(BN_ULONG res
[P256_LIMBS
],
1469 const BN_ULONG a
[P256_LIMBS
],
1472 static int ecp_nistz256_inv_mod_ord(const EC_GROUP
*group
, BIGNUM
*r
,
1473 const BIGNUM
*x
, BN_CTX
*ctx
)
1475 /* RR = 2^512 mod ord(p256) */
1476 static const BN_ULONG RR
[P256_LIMBS
] = {
1477 TOBN(0x83244c95,0xbe79eea2), TOBN(0x4699799c,0x49bd6fa6),
1478 TOBN(0x2845b239,0x2b6bec59), TOBN(0x66e12d94,0xf3d95620)
1480 /* The constant 1 (unlike ONE that is one in Montgomery representation) */
1481 static const BN_ULONG one
[P256_LIMBS
] = {
1482 TOBN(0,1), TOBN(0,0), TOBN(0,0), TOBN(0,0)
1485 * We don't use entry 0 in the table, so we omit it and address
1488 BN_ULONG table
[15][P256_LIMBS
];
1489 BN_ULONG out
[P256_LIMBS
], t
[P256_LIMBS
];
1492 i_1
= 0, i_10
, i_11
, i_101
, i_111
, i_1010
, i_1111
,
1493 i_10101
, i_101010
, i_101111
, i_x6
, i_x8
, i_x16
, i_x32
1497 * Catch allocation failure early.
1499 if (bn_wexpand(r
, P256_LIMBS
) == NULL
) {
1500 ECerr(EC_F_ECP_NISTZ256_INV_MOD_ORD
, ERR_R_BN_LIB
);
1504 if ((BN_num_bits(x
) > 256) || BN_is_negative(x
)) {
1507 if ((tmp
= BN_CTX_get(ctx
)) == NULL
1508 || !BN_nnmod(tmp
, x
, group
->order
, ctx
)) {
1509 ECerr(EC_F_ECP_NISTZ256_INV_MOD_ORD
, ERR_R_BN_LIB
);
1515 if (!ecp_nistz256_bignum_to_field_elem(t
, x
)) {
1516 ECerr(EC_F_ECP_NISTZ256_INV_MOD_ORD
, EC_R_COORDINATES_OUT_OF_RANGE
);
1520 ecp_nistz256_ord_mul_mont(table
[0], t
, RR
);
1523 * Original sparse-then-fixed-window algorithm, retained for reference.
1525 for (i
= 2; i
< 16; i
+= 2) {
1526 ecp_nistz256_ord_sqr_mont(table
[i
-1], table
[i
/2-1], 1);
1527 ecp_nistz256_ord_mul_mont(table
[i
], table
[i
-1], table
[0]);
1531 * The top 128bit of the exponent are highly redudndant, so we
1532 * perform an optimized flow
1534 ecp_nistz256_ord_sqr_mont(t
, table
[15-1], 4); /* f0 */
1535 ecp_nistz256_ord_mul_mont(t
, t
, table
[15-1]); /* ff */
1537 ecp_nistz256_ord_sqr_mont(out
, t
, 8); /* ff00 */
1538 ecp_nistz256_ord_mul_mont(out
, out
, t
); /* ffff */
1540 ecp_nistz256_ord_sqr_mont(t
, out
, 16); /* ffff0000 */
1541 ecp_nistz256_ord_mul_mont(t
, t
, out
); /* ffffffff */
1543 ecp_nistz256_ord_sqr_mont(out
, t
, 64); /* ffffffff0000000000000000 */
1544 ecp_nistz256_ord_mul_mont(out
, out
, t
); /* ffffffff00000000ffffffff */
1546 ecp_nistz256_ord_sqr_mont(out
, out
, 32); /* ffffffff00000000ffffffff00000000 */
1547 ecp_nistz256_ord_mul_mont(out
, out
, t
); /* ffffffff00000000ffffffffffffffff */
1550 * The bottom 128 bit of the exponent are processed with fixed 4-bit window
1552 for(i
= 0; i
< 32; i
++) {
1553 /* expLo - the low 128 bits of the exponent we use (ord(p256) - 2),
1554 * split into nibbles */
1555 static const unsigned char expLo
[32] = {
1556 0xb,0xc,0xe,0x6,0xf,0xa,0xa,0xd,0xa,0x7,0x1,0x7,0x9,0xe,0x8,0x4,
1557 0xf,0x3,0xb,0x9,0xc,0xa,0xc,0x2,0xf,0xc,0x6,0x3,0x2,0x5,0x4,0xf
1560 ecp_nistz256_ord_sqr_mont(out
, out
, 4);
1561 /* The exponent is public, no need in constant-time access */
1562 ecp_nistz256_ord_mul_mont(out
, out
, table
[expLo
[i
]-1]);
1566 * https://briansmith.org/ecc-inversion-addition-chains-01#p256_scalar_inversion
1568 * Even though this code path spares 12 squarings, 4.5%, and 13
1569 * multiplications, 25%, on grand scale sign operation is not that
1570 * much faster, not more that 2%...
1573 /* pre-calculate powers */
1574 ecp_nistz256_ord_sqr_mont(table
[i_10
], table
[i_1
], 1);
1576 ecp_nistz256_ord_mul_mont(table
[i_11
], table
[i_1
], table
[i_10
]);
1578 ecp_nistz256_ord_mul_mont(table
[i_101
], table
[i_11
], table
[i_10
]);
1580 ecp_nistz256_ord_mul_mont(table
[i_111
], table
[i_101
], table
[i_10
]);
1582 ecp_nistz256_ord_sqr_mont(table
[i_1010
], table
[i_101
], 1);
1584 ecp_nistz256_ord_mul_mont(table
[i_1111
], table
[i_1010
], table
[i_101
]);
1586 ecp_nistz256_ord_sqr_mont(table
[i_10101
], table
[i_1010
], 1);
1587 ecp_nistz256_ord_mul_mont(table
[i_10101
], table
[i_10101
], table
[i_1
]);
1589 ecp_nistz256_ord_sqr_mont(table
[i_101010
], table
[i_10101
], 1);
1591 ecp_nistz256_ord_mul_mont(table
[i_101111
], table
[i_101010
], table
[i_101
]);
1593 ecp_nistz256_ord_mul_mont(table
[i_x6
], table
[i_101010
], table
[i_10101
]);
1595 ecp_nistz256_ord_sqr_mont(table
[i_x8
], table
[i_x6
], 2);
1596 ecp_nistz256_ord_mul_mont(table
[i_x8
], table
[i_x8
], table
[i_11
]);
1598 ecp_nistz256_ord_sqr_mont(table
[i_x16
], table
[i_x8
], 8);
1599 ecp_nistz256_ord_mul_mont(table
[i_x16
], table
[i_x16
], table
[i_x8
]);
1601 ecp_nistz256_ord_sqr_mont(table
[i_x32
], table
[i_x16
], 16);
1602 ecp_nistz256_ord_mul_mont(table
[i_x32
], table
[i_x32
], table
[i_x16
]);
1605 ecp_nistz256_ord_sqr_mont(out
, table
[i_x32
], 64);
1606 ecp_nistz256_ord_mul_mont(out
, out
, table
[i_x32
]);
1608 for (i
= 0; i
< 27; i
++) {
1609 static const struct { unsigned char p
, i
; } chain
[27] = {
1610 { 32, i_x32
}, { 6, i_101111
}, { 5, i_111
},
1611 { 4, i_11
}, { 5, i_1111
}, { 5, i_10101
},
1612 { 4, i_101
}, { 3, i_101
}, { 3, i_101
},
1613 { 5, i_111
}, { 9, i_101111
}, { 6, i_1111
},
1614 { 2, i_1
}, { 5, i_1
}, { 6, i_1111
},
1615 { 5, i_111
}, { 4, i_111
}, { 5, i_111
},
1616 { 5, i_101
}, { 3, i_11
}, { 10, i_101111
},
1617 { 2, i_11
}, { 5, i_11
}, { 5, i_11
},
1618 { 3, i_1
}, { 7, i_10101
}, { 6, i_1111
}
1621 ecp_nistz256_ord_sqr_mont(out
, out
, chain
[i
].p
);
1622 ecp_nistz256_ord_mul_mont(out
, out
, table
[chain
[i
].i
]);
1625 ecp_nistz256_ord_mul_mont(out
, out
, one
);
1628 * Can't fail, but check return code to be consistent anyway.
1630 if (!bn_set_words(r
, out
, P256_LIMBS
))
1638 # define ecp_nistz256_inv_mod_ord NULL
1641 const EC_METHOD
*EC_GFp_nistz256_method(void)
1643 static const EC_METHOD ret
= {
1644 EC_FLAGS_DEFAULT_OCT
,
1645 NID_X9_62_prime_field
,
1646 ec_GFp_mont_group_init
,
1647 ec_GFp_mont_group_finish
,
1648 ec_GFp_mont_group_clear_finish
,
1649 ec_GFp_mont_group_copy
,
1650 ec_GFp_mont_group_set_curve
,
1651 ec_GFp_simple_group_get_curve
,
1652 ec_GFp_simple_group_get_degree
,
1653 ec_group_simple_order_bits
,
1654 ec_GFp_simple_group_check_discriminant
,
1655 ec_GFp_simple_point_init
,
1656 ec_GFp_simple_point_finish
,
1657 ec_GFp_simple_point_clear_finish
,
1658 ec_GFp_simple_point_copy
,
1659 ec_GFp_simple_point_set_to_infinity
,
1660 ec_GFp_simple_set_Jprojective_coordinates_GFp
,
1661 ec_GFp_simple_get_Jprojective_coordinates_GFp
,
1662 ec_GFp_simple_point_set_affine_coordinates
,
1663 ecp_nistz256_get_affine
,
1667 ec_GFp_simple_invert
,
1668 ec_GFp_simple_is_at_infinity
,
1669 ec_GFp_simple_is_on_curve
,
1671 ec_GFp_simple_make_affine
,
1672 ec_GFp_simple_points_make_affine
,
1673 ecp_nistz256_points_mul
, /* mul */
1674 ecp_nistz256_mult_precompute
, /* precompute_mult */
1675 ecp_nistz256_window_have_precompute_mult
, /* have_precompute_mult */
1676 ec_GFp_mont_field_mul
,
1677 ec_GFp_mont_field_sqr
,
1679 ec_GFp_mont_field_inv
,
1680 ec_GFp_mont_field_encode
,
1681 ec_GFp_mont_field_decode
,
1682 ec_GFp_mont_field_set_to_one
,
1683 ec_key_simple_priv2oct
,
1684 ec_key_simple_oct2priv
,
1685 0, /* set private */
1686 ec_key_simple_generate_key
,
1687 ec_key_simple_check_key
,
1688 ec_key_simple_generate_public_key
,
1691 ecdh_simple_compute_key
,
1692 ecdsa_simple_sign_setup
,
1693 ecdsa_simple_sign_sig
,
1694 ecdsa_simple_verify_sig
,
1695 ecp_nistz256_inv_mod_ord
, /* can be #define-d NULL */
1696 0, /* blind_coordinates */
1698 0, /* ladder_step */