Daniel Erat | 59c5f4b | 2015-08-24 12:50:25 -0600 | [diff] [blame] | 1 | // Copyright (c) 2013 The Chromium Authors. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
| 4 | |
| 5 | #include "crypto/curve25519.h" |
| 6 | |
| 7 | // Curve25519 is specified in terms of byte strings, not numbers, so all |
| 8 | // implementations take and return the same sequence of bits. So the byte |
| 9 | // order is implicitly specified as in, say, SHA1. |
| 10 | // |
| 11 | // Prototype for |curve25519_donna| function in |
| 12 | // third_party/curve25519-donna/curve25519-donna.c |
| 13 | extern "C" int curve25519_donna(uint8*, const uint8*, const uint8*); |
| 14 | |
| 15 | namespace crypto { |
| 16 | |
| 17 | namespace curve25519 { |
| 18 | |
| 19 | void ScalarMult(const uint8* private_key, |
| 20 | const uint8* peer_public_key, |
| 21 | uint8* shared_key) { |
| 22 | curve25519_donna(shared_key, private_key, peer_public_key); |
| 23 | } |
| 24 | |
| 25 | // kBasePoint is the base point (generator) of the elliptic curve group. |
| 26 | // It is little-endian version of '9' followed by 31 zeros. |
| 27 | // See "Computing public keys" section of http://cr.yp.to/ecdh.html. |
| 28 | static const unsigned char kBasePoint[32] = {9}; |
| 29 | |
| 30 | void ScalarBaseMult(const uint8* private_key, uint8* public_key) { |
| 31 | curve25519_donna(public_key, private_key, kBasePoint); |
| 32 | } |
| 33 | |
| 34 | } // namespace curve25519 |
| 35 | |
| 36 | } // namespace crypto |