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.
 
 
 
 
 

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/*
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 Message.h
* @author Gav Wood <i@gavwood.com>
* @date 2014
*/
#pragma once
#include <mutex>
#include <array>
#include <set>
#include <memory>
#include <utility>
#include <libdevcore/RLP.h>
#include <libdevcore/Guards.h>
#include <libdevcrypto/Common.h>
#include <libdevcore/SHA3.h>
#include "Common.h"
namespace dev
{
namespace shh
{
class Message;
static const unsigned Undefined = (unsigned)-1;
struct FilterKey
{
FilterKey() {}
FilterKey(unsigned _tI, Secret const& _k): topicIndex(_tI), key(_k) {}
unsigned topicIndex = Undefined;
Secret key;
};
enum IncludeNonce
{
WithoutNonce = 0,
WithNonce = 1
};
class Envelope
{
friend class Message;
public:
Envelope() {}
Envelope(RLP const& _m);
operator bool() const { return !!m_expiry; }
void streamRLP(RLPStream& _s, IncludeNonce _withNonce = WithNonce) const { _s.appendList(_withNonce ? 5 : 4) << m_expiry << m_ttl << m_topic << m_data; if (_withNonce) _s << m_nonce; }
h256 sha3(IncludeNonce _withNonce = WithNonce) const { RLPStream s; streamRLP(s, _withNonce); return dev::sha3(s.out()); }
unsigned sent() const { return m_expiry - m_ttl; }
unsigned expiry() const { return m_expiry; }
unsigned ttl() const { return m_ttl; }
CollapsedTopic const& topic() const { return m_topic; }
bytes const& data() const { return m_data; }
Message open(FullTopic const& _ft, Secret const& _s = Secret()) const;
unsigned workProved() const;
void proveWork(unsigned _ms);
private:
Envelope(unsigned _exp, unsigned _ttl, CollapsedTopic const& _topic): m_expiry(_exp), m_ttl(_ttl), m_topic(_topic) {}
unsigned m_expiry = 0;
unsigned m_ttl = 0;
u256 m_nonce;
CollapsedTopic m_topic;
bytes m_data;
};
enum /*Message Flags*/
{
ContainsSignature = 1
};
/// An (unencrypted) message, constructed from the combination of an Envelope, and, potentially,
/// a Secret key to decrypt the Message.
class Message
{
public:
Message() {}
Message(Envelope const& _e, FullTopic const& _ft, Secret const& _s = Secret());
Message(bytes const& _payload): m_payload(_payload) {}
Message(bytesConstRef _payload): m_payload(_payload.toBytes()) {}
Message(bytes&& _payload) { std::swap(_payload, m_payload); }
Public from() const { return m_from; }
Public to() const { return m_to; }
bytes const& payload() const { return m_payload; }
void setFrom(Public _from) { m_from = _from; }
void setTo(Public _to) { m_to = _to; }
void setPayload(bytes const& _payload) { m_payload = _payload; }
void setPayload(bytes&& _payload) { swap(m_payload, _payload); }
operator bool() const { return !!m_payload.size() || m_from || m_to; }
/// Turn this message into a ditributable Envelope.
Envelope seal(Secret _from, FullTopic const& _topic, unsigned _ttl = 50, unsigned _workToProve = 50) const;
// Overloads for skipping _from or specifying _to.
Envelope seal(FullTopic const& _topic, unsigned _ttl = 50, unsigned _workToProve = 50) const { return seal(Secret(), _topic, _ttl, _workToProve); }
Envelope sealTo(Public _to, FullTopic const& _topic, unsigned _ttl = 50, unsigned _workToProve = 50) { m_to = _to; return seal(Secret(), _topic, _ttl, _workToProve); }
Envelope sealTo(Secret _from, Public _to, FullTopic const& _topic, unsigned _ttl = 50, unsigned _workToProve = 50) { m_to = _to; return seal(_from, _topic, _ttl, _workToProve); }
private:
bool populate(bytes const& _data);
bool openBroadcastEnvelope(Envelope const& _e, FullTopic const& _fk, bytes& o_b);
h256 generateGamma(h256 const& _key, h256 const& _salt) const { return sha3(_key ^ _salt); }
Public m_from;
Public m_to;
bytes m_payload;
};
}
}