aboutsummaryrefslogtreecommitdiffstats
path: root/src/libcryptobox/curve25519/curve25519.c
blob: 1d04b973baddeb598740fd9717a6453b77d16bc3 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
/*
 * Copyright (c) 2015, Vsevolod Stakhov
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *	 * Redistributions of source code must retain the above copyright
 *	   notice, this list of conditions and the following disclaimer.
 *	 * Redistributions in binary form must reproduce the above copyright
 *	   notice, this list of conditions and the following disclaimer in the
 *	   documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY AUTHOR ''AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL AUTHOR BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "config.h"
#include "cryptobox.h"
#include "curve25519.h"
#include "platform_config.h"

extern unsigned long cpu_config;

typedef struct curve25519_impl_s {
	unsigned long cpu_flags;
	const char *desc;

	void (*scalarmult) (guint8 *mypublic,
			const guint8 *secret,
			const guint8 *basepoint);
} curve25519_impl_t;

#define CURVE25519_DECLARE(ext) \
    void scalarmult_##ext(guint8 *mypublic, const guint8 *secret, const guint8 *basepoint)

#define CURVE25519_IMPL(cpuflags, desc, ext) \
    {(cpuflags), desc, scalarmult_##ext}

#if defined(__LP64__)
#if defined(HAVE_AVX)
CURVE25519_DECLARE(avx);
#define CURVE25519_AVX CURVE25519_IMPL(CPUID_AVX, "avx", avx)
#endif

#endif

CURVE25519_DECLARE(ref);
#define CURVE25519_REF CURVE25519_IMPL(0, "ref", ref)

#if (ARCH == x86_64) || (ARCH == i386)
CURVE25519_DECLARE(donna);
#define CURVE25519_GENERIC CURVE25519_IMPL(0, "donna", donna)
#else
#define CURVE25519_GENERIC CURVE25519_REF
#endif


static const curve25519_impl_t curve25519_list[] = {
		CURVE25519_GENERIC,
#if defined(CURVE25519_AVX)
		CURVE25519_AVX,
#endif
};

const guchar secA[] = {0x5A, 0xC9, 0x9F, 0x33, 0x63, 0x2E, 0x5A, 0x76, 0x8D,
					   0xE7, 0xE8, 0x1B, 0xF8, 0x54, 0xC2, 0x7C, 0x46, 0xE3,
					   0xFB, 0xF2, 0xAB, 0xBA, 0xCD, 0x29, 0xEC, 0x4A, 0xFF,
					   0x51, 0x73, 0x69, 0xC6, 0x60};
const guchar secB[] = {0x47, 0xDC, 0x3D, 0x21, 0x41, 0x74, 0x82, 0x0E, 0x11,
					   0x54, 0xB4, 0x9B, 0xC6, 0xCD, 0xB2, 0xAB, 0xD4, 0x5E,
					   0xE9, 0x58, 0x17, 0x05, 0x5D, 0x25, 0x5A, 0xA3, 0x58,
					   0x31, 0xB7, 0x0D, 0x32, 0x60};

static const curve25519_impl_t *curve25519_opt = &curve25519_list[0];

static gboolean
curve25519_test_impl (const curve25519_impl_t *impl)
{
	guchar sec_local[32], sec_ref[32],
		pubA[32], pubB[32];

	curve25519_impl_t ref_impl = CURVE25519_REF;

	ref_impl.scalarmult (pubA, secA, curve25519_basepoint);
	ref_impl.scalarmult (pubB, secB, curve25519_basepoint);

	impl->scalarmult (sec_local, secA, pubB);
	ref_impl.scalarmult (sec_ref, secA, pubB);

	if (memcmp (sec_local, sec_ref, sizeof (sec_ref)) != 0) {
		return FALSE;
	}

	impl->scalarmult (sec_local, secB, pubA);
	ref_impl.scalarmult (sec_ref, secB, pubA);

	if (memcmp (sec_local, sec_ref, sizeof (sec_ref)) != 0) {
		return FALSE;
	}

	impl->scalarmult (sec_local, secB, pubA);
	impl->scalarmult (sec_ref, secA, pubB);

	if (memcmp (sec_local, sec_ref, sizeof (sec_ref)) != 0) {
		return FALSE;
	}

	return TRUE;
}

void
curve25519_load (void)
{
	guint i;

	if (cpu_config != 0) {
		for (i = 0; i < G_N_ELEMENTS(curve25519_list); i++) {
			if (curve25519_list[i].cpu_flags & cpu_config) {
				curve25519_opt = &curve25519_list[i];
				break;
			}
		}
	}
	g_assert (curve25519_test_impl (curve25519_opt));
}

int
curve25519 (guchar *mypublic,
		const guchar *secret,
		const guchar *basepoint)
{
	curve25519_opt->scalarmult (mypublic, secret, basepoint);

	return 0;
}