/*
* ZeroTier One - Network Virtualization Everywhere
* Copyright (C) 2011-2016 ZeroTier, Inc. https://www.zerotier.com/
*
* This program 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.
*
* This program 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 this program. If not, see .
*/
#ifndef ZT_INCOMINGPACKET_HPP
#define ZT_INCOMINGPACKET_HPP
#include
#include "Packet.hpp"
#include "InetAddress.hpp"
#include "Utils.hpp"
#include "MulticastGroup.hpp"
#include "Peer.hpp"
/*
* The big picture:
*
* tryDecode gets called for a given fully-assembled packet until it returns
* true or the packet's time to live has been exceeded, in which case it is
* discarded as failed decode. Any exception thrown by tryDecode also causes
* the packet to be discarded.
*
* Thus a return of false from tryDecode() indicates that it should be called
* again. Logic is very simple as to when, and it's in doAnythingWaitingForPeer
* in Switch. This might be expanded to be more fine grained in the future.
*
* A return value of true indicates that the packet is done. tryDecode must
* never be called again after that.
*/
namespace ZeroTier {
class RuntimeEnvironment;
class Network;
/**
* Subclass of packet that handles the decoding of it
*/
class IncomingPacket : public Packet
{
public:
IncomingPacket() :
Packet(),
_receiveTime(0),
_localAddress(),
_remoteAddress()
{
}
IncomingPacket(const IncomingPacket &p)
{
// All fields including InetAddress are memcpy'able
memcpy(this,&p,sizeof(IncomingPacket));
}
/**
* Create a new packet-in-decode
*
* @param data Packet data
* @param len Packet length
* @param localAddress Local interface address
* @param remoteAddress Address from which packet came
* @param now Current time
* @throws std::out_of_range Range error processing packet
*/
IncomingPacket(const void *data,unsigned int len,const InetAddress &localAddress,const InetAddress &remoteAddress,uint64_t now) :
Packet(data,len),
_receiveTime(now),
_localAddress(localAddress),
_remoteAddress(remoteAddress)
{
}
inline IncomingPacket &operator=(const IncomingPacket &p)
{
// All fields including InetAddress are memcpy'able
memcpy(this,&p,sizeof(IncomingPacket));
return *this;
}
/**
* Init packet-in-decode in place
*
* @param data Packet data
* @param len Packet length
* @param localAddress Local interface address
* @param remoteAddress Address from which packet came
* @param now Current time
* @throws std::out_of_range Range error processing packet
*/
inline void init(const void *data,unsigned int len,const InetAddress &localAddress,const InetAddress &remoteAddress,uint64_t now)
{
copyFrom(data,len);
_receiveTime = now;
_localAddress = localAddress;
_remoteAddress = remoteAddress;
}
/**
* Attempt to decode this packet
*
* Note that this returns 'true' if processing is complete. This says nothing
* about whether the packet was valid. A rejection is 'complete.'
*
* Once true is returned, this must not be called again. The packet's state
* may no longer be valid. The only exception is deferred decoding. In this
* case true is returned to indicate to the normal decode path that it is
* finished with the packet. The packet will have added itself to the
* deferred queue and will expect tryDecode() to be called one more time
* with deferred set to true.
*
* Deferred decoding is performed by DeferredPackets.cpp and should not be
* done elsewhere. Under deferred decoding packets only get one shot and
* so the return value of tryDecode() is ignored.
*
* @param RR Runtime environment
* @param deferred If true, this is a deferred decode and the return is ignored
* @return True if decoding and processing is complete, false if caller should try again
*/
bool tryDecode(const RuntimeEnvironment *RR,bool deferred);
/**
* @return Time of packet receipt / start of decode
*/
inline uint64_t receiveTime() const throw() { return _receiveTime; }
/**
* Compute the Salsa20/12+SHA512 proof of work function
*
* @param difficulty Difficulty in bits (max: 64)
* @param challenge Challenge string
* @param challengeLength Length of challenge in bytes (max allowed: ZT_PROTO_MAX_PACKET_LENGTH)
* @param result Buffer to fill with 16-byte result
*/
static void computeSalsa2012Sha512ProofOfWork(unsigned int difficulty,const void *challenge,unsigned int challengeLength,unsigned char result[16]);
/**
* Verify the result of Salsa20/12+SHA512 proof of work
*
* @param difficulty Difficulty in bits (max: 64)
* @param challenge Challenge bytes
* @param challengeLength Length of challenge in bytes (max allowed: ZT_PROTO_MAX_PACKET_LENGTH)
* @param proposedResult Result supplied by client
* @return True if result is valid
*/
static bool testSalsa2012Sha512ProofOfWorkResult(unsigned int difficulty,const void *challenge,unsigned int challengeLength,const unsigned char proposedResult[16]);
private:
// These are called internally to handle packet contents once it has
// been authenticated, decrypted, decompressed, and classified.
bool _doERROR(const RuntimeEnvironment *RR,const SharedPtr &peer);
bool _doHELLO(const RuntimeEnvironment *RR,SharedPtr &peer); // can be called with NULL peer, while all others cannot
bool _doOK(const RuntimeEnvironment *RR,const SharedPtr &peer);
bool _doWHOIS(const RuntimeEnvironment *RR,const SharedPtr &peer);
bool _doRENDEZVOUS(const RuntimeEnvironment *RR,const SharedPtr &peer);
bool _doFRAME(const RuntimeEnvironment *RR,const SharedPtr &peer);
bool _doEXT_FRAME(const RuntimeEnvironment *RR,const SharedPtr &peer);
bool _doECHO(const RuntimeEnvironment *RR,const SharedPtr &peer);
bool _doMULTICAST_LIKE(const RuntimeEnvironment *RR,const SharedPtr &peer);
bool _doNETWORK_CREDENTIALS(const RuntimeEnvironment *RR,const SharedPtr &peer);
bool _doNETWORK_CONFIG_REQUEST(const RuntimeEnvironment *RR,const SharedPtr &peer);
bool _doMULTICAST_GATHER(const RuntimeEnvironment *RR,const SharedPtr &peer);
bool _doMULTICAST_FRAME(const RuntimeEnvironment *RR,const SharedPtr &peer);
bool _doPUSH_DIRECT_PATHS(const RuntimeEnvironment *RR,const SharedPtr &peer);
bool _doCIRCUIT_TEST(const RuntimeEnvironment *RR,const SharedPtr &peer);
bool _doCIRCUIT_TEST_REPORT(const RuntimeEnvironment *RR,const SharedPtr &peer);
bool _doREQUEST_PROOF_OF_WORK(const RuntimeEnvironment *RR,const SharedPtr &peer);
uint64_t _receiveTime;
InetAddress _localAddress;
InetAddress _remoteAddress;
};
} // namespace ZeroTier
#endif