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 37
