You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
81 lines
2.1 KiB
81 lines
2.1 KiB
/*
|
|
This file is part of cpp-ethereum.
|
|
|
|
cpp-ethereum is free software: you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation, either version 3 of the License, or
|
|
(at your option) any later version.
|
|
|
|
cpp-ethereum is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with cpp-ethereum. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
/** @file ECDHE.h
|
|
* @author Alex Leverington <nessence@gmail.com>
|
|
* @date 2014
|
|
*
|
|
* Elliptic curve Diffie-Hellman ephemeral key exchange
|
|
*/
|
|
|
|
#pragma once
|
|
|
|
#include "AES.h"
|
|
|
|
namespace dev
|
|
{
|
|
namespace crypto
|
|
{
|
|
|
|
/// Public key of remote and corresponding shared secret.
|
|
using AliasSession = std::pair<Public,h256>;
|
|
|
|
/**
|
|
* @brief An addressable EC key pair.
|
|
*/
|
|
class Alias
|
|
{
|
|
public:
|
|
Alias(Secret const& _s): m_secret(_s) {};
|
|
|
|
AliasSession session(Address _a) { return m_sessions.count(_a) ? m_sessions.find(_a)->second : AliasSession(); }
|
|
|
|
private:
|
|
std::map<Address,AliasSession> m_sessions;
|
|
Secret m_secret;
|
|
};
|
|
|
|
namespace ecdh
|
|
{
|
|
void agree(Secret const& _s, Public const& _r, h256& o_s);
|
|
}
|
|
|
|
/**
|
|
* @brief Derive DH shared secret from EC keypairs.
|
|
* As ephemeral keys are single-use, agreement is limited to a single occurence.
|
|
*/
|
|
class ECDHE
|
|
{
|
|
public:
|
|
/// Constructor (pass public key for ingress exchange).
|
|
ECDHE(): m_ephemeral(KeyPair::create()) {};
|
|
|
|
/// Public key sent to remote.
|
|
Public pubkey() { return m_ephemeral.pub(); }
|
|
|
|
Secret seckey() { return m_ephemeral.sec(); }
|
|
|
|
/// Input public key for dh agreement, output generated shared secret.
|
|
void agree(Public const& _remoteEphemeral, Secret& o_sharedSecret) const;
|
|
|
|
protected:
|
|
KeyPair m_ephemeral; ///< Ephemeral keypair; generated.
|
|
mutable Public m_remoteEphemeral; ///< Public key of remote; parameter. Set once when agree is called, otherwise immutable.
|
|
};
|
|
|
|
}
|
|
}
|
|
|
|
|