1 /* Copyright (c) 2014, Intel Corporation.
2 *
3 * Permission to use, copy, modify, and/or distribute this software for any
4 * purpose with or without fee is hereby granted, provided that the above
5 * copyright notice and this permission notice appear in all copies.
6 *
7 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
8 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
9 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
10 * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
11 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
12 * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
13 * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
14
15 #ifndef OPENSSL_HEADER_EC_P256_X86_64_H
16 #define OPENSSL_HEADER_EC_P256_X86_64_H
17
18 #include <openssl/base.h>
19
20 #include <openssl/bn.h>
21
22 #if defined(__cplusplus)
23 extern "C" {
24 #endif
25
26
27 #if !defined(OPENSSL_NO_ASM) && defined(OPENSSL_X86_64) && \
28 !defined(OPENSSL_SMALL)
29
30 // P-256 field operations.
31 //
32 // An element mod P in P-256 is represented as a little-endian array of
33 // |P256_LIMBS| |BN_ULONG|s, spanning the full range of values.
34 //
35 // The following functions take fully-reduced inputs mod P and give
36 // fully-reduced outputs. They may be used in-place.
37
38 #define P256_LIMBS (256 / BN_BITS2)
39
40 // ecp_nistz256_neg sets |res| to -|a| mod P.
41 void ecp_nistz256_neg(BN_ULONG res[P256_LIMBS], const BN_ULONG a[P256_LIMBS]);
42
43 // ecp_nistz256_mul_mont sets |res| to |a| * |b| * 2^-256 mod P.
44 void ecp_nistz256_mul_mont(BN_ULONG res[P256_LIMBS],
45 const BN_ULONG a[P256_LIMBS],
46 const BN_ULONG b[P256_LIMBS]);
47
48 // ecp_nistz256_sqr_mont sets |res| to |a| * |a| * 2^-256 mod P.
49 void ecp_nistz256_sqr_mont(BN_ULONG res[P256_LIMBS],
50 const BN_ULONG a[P256_LIMBS]);
51
52 // ecp_nistz256_from_mont sets |res| to |in|, converted from Montgomery domain
53 // by multiplying with 1.
ecp_nistz256_from_mont(BN_ULONG res[P256_LIMBS],const BN_ULONG in[P256_LIMBS])54 static inline void ecp_nistz256_from_mont(BN_ULONG res[P256_LIMBS],
55 const BN_ULONG in[P256_LIMBS]) {
56 static const BN_ULONG ONE[P256_LIMBS] = { 1 };
57 ecp_nistz256_mul_mont(res, in, ONE);
58 }
59
60
61 // P-256 point operations.
62 //
63 // The following functions may be used in-place. All coordinates are in the
64 // Montgomery domain.
65
66 // A P256_POINT represents a P-256 point in Jacobian coordinates.
67 typedef struct {
68 BN_ULONG X[P256_LIMBS];
69 BN_ULONG Y[P256_LIMBS];
70 BN_ULONG Z[P256_LIMBS];
71 } P256_POINT;
72
73 // A P256_POINT_AFFINE represents a P-256 point in affine coordinates. Infinity
74 // is encoded as (0, 0).
75 typedef struct {
76 BN_ULONG X[P256_LIMBS];
77 BN_ULONG Y[P256_LIMBS];
78 } P256_POINT_AFFINE;
79
80 // ecp_nistz256_select_w5 sets |*val| to |in_t[index-1]| if 1 <= |index| <= 16
81 // and all zeros (the point at infinity) if |index| is 0. This is done in
82 // constant time.
83 void ecp_nistz256_select_w5(P256_POINT *val, const P256_POINT in_t[16],
84 int index);
85
86 // ecp_nistz256_select_w7 sets |*val| to |in_t[index-1]| if 1 <= |index| <= 64
87 // and all zeros (the point at infinity) if |index| is 0. This is done in
88 // constant time.
89 void ecp_nistz256_select_w7(P256_POINT_AFFINE *val,
90 const P256_POINT_AFFINE in_t[64], int index);
91
92 // ecp_nistz256_point_double sets |r| to |a| doubled.
93 void ecp_nistz256_point_double(P256_POINT *r, const P256_POINT *a);
94
95 // ecp_nistz256_point_add adds |a| to |b| and places the result in |r|.
96 void ecp_nistz256_point_add(P256_POINT *r, const P256_POINT *a,
97 const P256_POINT *b);
98
99 // ecp_nistz256_point_add_affine adds |a| to |b| and places the result in
100 // |r|. |a| and |b| must not represent the same point unless they are both
101 // infinity.
102 void ecp_nistz256_point_add_affine(P256_POINT *r, const P256_POINT *a,
103 const P256_POINT_AFFINE *b);
104
105 #endif /* !defined(OPENSSL_NO_ASM) && defined(OPENSSL_X86_64) && \
106 !defined(OPENSSL_SMALL) */
107
108
109 #if defined(__cplusplus)
110 } // extern C++
111 #endif
112
113 #endif // OPENSSL_HEADER_EC_P256_X86_64_H
114