| 1 |
root |
1.1 |
/* |
| 2 |
|
|
curve25519.C -- diffie hellman key exchange |
| 3 |
|
|
Copyright (C) 2013 Marc Lehmann <gvpe@schmorp.de> |
| 4 |
|
|
|
| 5 |
|
|
This file is part of GVPE. |
| 6 |
|
|
|
| 7 |
|
|
GVPE is free software; you can redistribute it and/or modify it |
| 8 |
|
|
under the terms of the GNU General Public License as published by the |
| 9 |
|
|
Free Software Foundation; either version 3 of the License, or (at your |
| 10 |
|
|
option) any later version. |
| 11 |
|
|
|
| 12 |
|
|
This program is distributed in the hope that it will be useful, but |
| 13 |
|
|
WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 |
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General |
| 15 |
|
|
Public License for more details. |
| 16 |
|
|
|
| 17 |
|
|
You should have received a copy of the GNU General Public License along |
| 18 |
|
|
with this program; if not, see <http://www.gnu.org/licenses/>. |
| 19 |
|
|
|
| 20 |
|
|
Additional permission under GNU GPL version 3 section 7 |
| 21 |
|
|
|
| 22 |
|
|
If you modify this Program, or any covered work, by linking or |
| 23 |
|
|
combining it with the OpenSSL project's OpenSSL library (or a modified |
| 24 |
|
|
version of that library), containing parts covered by the terms of the |
| 25 |
|
|
OpenSSL or SSLeay licenses, the licensors of this Program grant you |
| 26 |
|
|
additional permission to convey the resulting work. Corresponding |
| 27 |
|
|
Source for a non-source form of such a combination shall include the |
| 28 |
|
|
source code for the parts of OpenSSL used as well as that of the |
| 29 |
|
|
covered work. |
| 30 |
|
|
*/ |
| 31 |
|
|
|
| 32 |
|
|
#include "config.h" |
| 33 |
|
|
|
| 34 |
|
|
#include <cstring> |
| 35 |
|
|
#include <openssl/rand.h> |
| 36 |
|
|
|
| 37 |
|
|
#include "util.h" |
| 38 |
|
|
#include "curve25519.h" |
| 39 |
|
|
#include "curve25519-donna.c" |
| 40 |
|
|
|
| 41 |
|
|
static void |
| 42 |
|
|
curve25519_derive (const curve25519_key &a, curve25519_key &b) |
| 43 |
|
|
{ |
| 44 |
|
|
static const curve25519_key basepoint = { 9 }; |
| 45 |
|
|
curve25519_donna (b, a, basepoint); |
| 46 |
|
|
} |
| 47 |
|
|
|
| 48 |
|
|
void curve25519_generate (curve25519_key &a, curve25519_key &b) |
| 49 |
|
|
{ |
| 50 |
root |
1.2 |
RAND_bytes (a, sizeof a); |
| 51 |
root |
1.1 |
|
| 52 |
|
|
a [ 0] &= 0xf8; |
| 53 |
|
|
a [31] &= 0x7f; |
| 54 |
|
|
a [31] |= 0x40; |
| 55 |
|
|
|
| 56 |
|
|
curve25519_derive (a, b); |
| 57 |
|
|
} |
| 58 |
|
|
|
| 59 |
|
|
void curve25519_combine (const curve25519_key &a, const curve25519_key &b, curve25519_key &s) |
| 60 |
|
|
{ |
| 61 |
|
|
curve25519_donna (s, a, b); |
| 62 |
|
|
} |
| 63 |
|
|
|
| 64 |
|
|
void curve25519_verify () |
| 65 |
|
|
{ |
| 66 |
|
|
// NaCl test vector |
| 67 |
|
|
|
| 68 |
|
|
static const curve25519_key alice_private = { 0x77, 0x07, 0x6d, 0x0a, 0x73, 0x18, 0xa5, 0x7d, 0x3c, 0x16, 0xc1, 0x72, 0x51, 0xb2, 0x66, 0x45, 0xdf, 0x4c, 0x2f, 0x87, 0xeb, 0xc0, 0x99, 0x2a, 0xb1, 0x77, 0xfb, 0xa5, 0x1d, 0xb9, 0x2c, 0x2a }; |
| 69 |
|
|
static const curve25519_key alice_public = { 0x85, 0x20, 0xf0, 0x09, 0x89, 0x30, 0xa7, 0x54, 0x74, 0x8b, 0x7d, 0xdc, 0xb4, 0x3e, 0xf7, 0x5a, 0x0d, 0xbf, 0x3a, 0x0d, 0x26, 0x38, 0x1a, 0xf4, 0xeb, 0xa4, 0xa9, 0x8e, 0xaa, 0x9b, 0x4e, 0x6a }; |
| 70 |
|
|
static const curve25519_key bob_private = { 0x5d, 0xab, 0x08, 0x7e, 0x62, 0x4a, 0x8a, 0x4b, 0x79, 0xe1, 0x7f, 0x8b, 0x83, 0x80, 0x0e, 0xe6, 0x6f, 0x3b, 0xb1, 0x29, 0x26, 0x18, 0xb6, 0xfd, 0x1c, 0x2f, 0x8b, 0x27, 0xff, 0x88, 0xe0, 0xeb }; |
| 71 |
|
|
static const curve25519_key bob_public = { 0xde, 0x9e, 0xdb, 0x7d, 0x7b, 0x7d, 0xc1, 0xb4, 0xd3, 0x5b, 0x61, 0xc2, 0xec, 0xe4, 0x35, 0x37, 0x3f, 0x83, 0x43, 0xc8, 0x5b, 0x78, 0x67, 0x4d, 0xad, 0xfc, 0x7e, 0x14, 0x6f, 0x88, 0x2b, 0x4f }; |
| 72 |
|
|
static const curve25519_key alice_mult_bob = { 0x4a, 0x5d, 0x9d, 0x5b, 0xa4, 0xce, 0x2d, 0xe1, 0x72, 0x8e, 0x3b, 0xf4, 0x80, 0x35, 0x0f, 0x25, 0xe0, 0x7e, 0x21, 0xc9, 0x47, 0xd1, 0x9e, 0x33, 0x76, 0xf0, 0x9b, 0x3c, 0x1e, 0x16, 0x17, 0x42 }; |
| 73 |
|
|
|
| 74 |
|
|
curve25519_key a, b, s1, s2; |
| 75 |
|
|
|
| 76 |
|
|
curve25519_derive (alice_private, a); |
| 77 |
|
|
curve25519_derive (bob_private , b); |
| 78 |
|
|
curve25519_combine (alice_private, b, s1); |
| 79 |
|
|
curve25519_combine (bob_private , a, s2); |
| 80 |
|
|
|
| 81 |
|
|
require (!memcmp (alice_public , a , sizeof a )); |
| 82 |
|
|
require (!memcmp (bob_public , b , sizeof b )); |
| 83 |
|
|
require (!memcmp (alice_mult_bob, s1, sizeof s1)); |
| 84 |
|
|
require (!memcmp (alice_mult_bob, s2, sizeof s2)); |
| 85 |
|
|
} |
| 86 |
|
|
|
