1 /*
2  * Copyright 2014-2016 The OpenSSL Project Authors. All Rights Reserved.
3  * Copyright (c) 2014, Intel Corporation. All Rights Reserved.
4  *
5  * Licensed under the OpenSSL license (the "License").  You may not use
6  * this file except in compliance with the License.  You can obtain a copy
7  * in the file LICENSE in the source distribution or at
8  * https://www.openssl.org/source/license.html
9  *
10  * Originally written by Shay Gueron (1, 2), and Vlad Krasnov (1)
11  * (1) Intel Corporation, Israel Development Center, Haifa, Israel
12  * (2) University of Haifa, Israel
13  *
14  * Reference:
15  * S.Gueron and V.Krasnov, "Fast Prime Field Elliptic Curve Cryptography with
16  *                          256 Bit Primes"
17  */
18 
19 #ifndef OPENSSL_HEADER_EC_P256_X86_64_H
20 #define OPENSSL_HEADER_EC_P256_X86_64_H
21 
22 #include <ring-core/base.h>
23 
24 #include "p256_shared.h"
25 
26 #include "../bn/internal.h"
27 
28 #if defined(OPENSSL_USE_NISTZ256)
29 
30 // ecp_nistz256_neg sets |res| to -|a| mod P.
31 void ecp_nistz256_neg(BN_ULONG res[P256_LIMBS], const BN_ULONG a[P256_LIMBS]);
32 
33 // ecp_nistz256_mul_mont sets |res| to |a| * |b| * 2^-256 mod P.
34 void ecp_nistz256_mul_mont(BN_ULONG res[P256_LIMBS],
35                            const BN_ULONG a[P256_LIMBS],
36                            const BN_ULONG b[P256_LIMBS]);
37 
38 // ecp_nistz256_sqr_mont sets |res| to |a| * |a| * 2^-256 mod P.
39 void ecp_nistz256_sqr_mont(BN_ULONG res[P256_LIMBS],
40                            const BN_ULONG a[P256_LIMBS]);
41 
42 
43 // P-256 scalar operations.
44 //
45 // The following functions compute modulo N, where N is the order of P-256. They
46 // take fully-reduced inputs and give fully-reduced outputs.
47 
48 // ecp_nistz256_ord_mul_mont sets |res| to |a| * |b| where inputs and outputs
49 // are in Montgomery form. That is, |res| is |a| * |b| * 2^-256 mod N.
50 void ecp_nistz256_ord_mul_mont(BN_ULONG res[P256_LIMBS],
51                                const BN_ULONG a[P256_LIMBS],
52                                const BN_ULONG b[P256_LIMBS]);
53 
54 // ecp_nistz256_ord_sqr_mont sets |res| to |a|^(2*|rep|) where inputs and
55 // outputs are in Montgomery form. That is, |res| is
56 // (|a| * 2^-256)^(2*|rep|) * 2^256 mod N.
57 void ecp_nistz256_ord_sqr_mont(BN_ULONG res[P256_LIMBS],
58                                const BN_ULONG a[P256_LIMBS], BN_ULONG rep);
59 
60 
61 
62 // P-256 point operations.
63 //
64 // The following functions may be used in-place. All coordinates are in the
65 // Montgomery domain.
66 
67 // A P256_POINT_AFFINE represents a P-256 point in affine coordinates. Infinity
68 // is encoded as (0, 0).
69 typedef struct {
70   BN_ULONG X[P256_LIMBS];
71   BN_ULONG Y[P256_LIMBS];
72 } P256_POINT_AFFINE;
73 
74 // ecp_nistz256_select_w5 sets |*val| to |in_t[index-1]| if 1 <= |index| <= 16
75 // and all zeros (the point at infinity) if |index| is 0. This is done in
76 // constant time.
77 void ecp_nistz256_select_w5(P256_POINT *val, const P256_POINT in_t[16],
78                             int index);
79 
80 // ecp_nistz256_select_w7 sets |*val| to |in_t[index-1]| if 1 <= |index| <= 64
81 // and all zeros (the point at infinity) if |index| is 0. This is done in
82 // constant time.
83 void ecp_nistz256_select_w7(P256_POINT_AFFINE *val,
84                             const P256_POINT_AFFINE in_t[64],
85                             int index);
86 
87 // ecp_nistz256_point_double sets |r| to |a| doubled.
88 void ecp_nistz256_point_double(P256_POINT *r, const P256_POINT *a);
89 
90 // ecp_nistz256_point_add adds |a| to |b| and places the result in |r|.
91 void ecp_nistz256_point_add(P256_POINT *r, const P256_POINT *a,
92                             const P256_POINT *b);
93 
94 // ecp_nistz256_point_add_affine adds |a| to |b| and places the result in
95 // |r|. |a| and |b| must not represent the same point unless they are both
96 // infinity.
97 void ecp_nistz256_point_add_affine(P256_POINT *r, const P256_POINT *a,
98                                    const P256_POINT_AFFINE *b);
99 
100 #endif /* defined(OPENSSL_USE_NISTZ256) */
101 
102 #endif  // OPENSSL_HEADER_EC_P256_X86_64_H
103