ZeroTierOne/node/Switch.hpp

271 lines
8.6 KiB
C++

/*
* ZeroTier One - Global Peer to Peer Ethernet
* Copyright (C) 2012-2013 ZeroTier Networks LLC
*
* 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 <http://www.gnu.org/licenses/>.
*
* --
*
* ZeroTier may be used and distributed under the terms of the GPLv3, which
* are available at: http://www.gnu.org/licenses/gpl-3.0.html
*
* If you would like to embed ZeroTier into a commercial application or
* redistribute it in a modified binary form, please contact ZeroTier Networks
* LLC. Start here: http://www.zerotier.com/
*/
#ifndef _ZT_N_SWITCH_HPP
#define _ZT_N_SWITCH_HPP
#include <map>
#include <set>
#include <vector>
#include "Mutex.hpp"
#include "MAC.hpp"
#include "NonCopyable.hpp"
#include "Constants.hpp"
#include "Packet.hpp"
#include "Utils.hpp"
#include "InetAddress.hpp"
#include "Topology.hpp"
#include "Array.hpp"
#include "Network.hpp"
#include "SharedPtr.hpp"
#include "Demarc.hpp"
namespace ZeroTier {
class RuntimeEnvironment;
class EthernetTap;
class Logger;
class Node;
class Peer;
/**
* Core of the distributed Ethernet switch and protocol implementation
*/
class Switch : NonCopyable
{
public:
Switch(const RuntimeEnvironment *renv);
~Switch();
/**
* Called when a packet is received from the real network
*
* @param localPort Local port on which packet was received
* @param fromAddr Internet IP address of origin
* @param data Packet data
*/
void onRemotePacket(Demarc::Port localPort,const InetAddress &fromAddr,const Buffer<4096> &data);
/**
* Called when a packet comes from a local Ethernet tap
*
* @param network Which network's TAP did this packet come from?
* @param from Originating MAC address
* @param to Destination MAC address
* @param etherType Ethernet packet type
* @param data Ethernet payload
*/
void onLocalEthernet(const SharedPtr<Network> &network,const MAC &from,const MAC &to,unsigned int etherType,const Buffer<4096> &data);
/**
* Send a packet to a ZeroTier address (destination in packet)
*
* The packet must be fully composed with source and destination but not
* yet encrypted. If the destination peer is known the packet
* is sent immediately. Otherwise it is queued and a WHOIS is dispatched.
*
* The packet may be compressed. Compression isn't done here.
*
* Needless to say, the packet's source must be this node. Otherwise it
* won't be encrypted right. (This is not used for relaying.)
*
* @param packet Packet to send
* @param encrypt Encrypt packet payload? (always true except for HELLO)
*/
void send(const Packet &packet,bool encrypt);
/**
* Send a HELLO announcement
*
* @param dest Address of destination
*/
void sendHELLO(const Address &dest);
/**
* Send a HELLO announcement immediately to the indicated address
*
* @param localPort Originating local port or ANY_PORT to pick
* @param addr IP address to send to
* @param dest Destination peer
* @return True if send appears successful
*/
bool sendHELLO(const SharedPtr<Peer> &dest,Demarc::Port localPort,const InetAddress &addr);
/**
* Send RENDEZVOUS to two peers to permit them to directly connect
*
* This only works if both peers are known, with known working direct
* links to this peer. The best link for each peer is sent to the other.
*
* A rate limiter is in effect via the _lastUniteAttempt map. If force
* is true, a unite attempt is made even if one has been made less than
* ZT_MIN_UNITE_INTERVAL milliseconds ago.
*
* @param p1 One of two peers (order doesn't matter)
* @param p2 Second of pair
* @param force If true, send now regardless of interval
*/
bool unite(const Address &p1,const Address &p2,bool force);
/**
* Perform retries and other periodic timer tasks
*
* @return Number of milliseconds until doTimerTasks() should be run again
*/
unsigned long doTimerTasks();
/**
* Announce multicast group memberships
*
* This efficiently announces memberships, sending single packets with
* many LIKEs.
*
* @param allMemberships Memberships for a number of networks
*/
void announceMulticastGroups(const std::map< SharedPtr<Network>,std::set<MulticastGroup> > &allMemberships);
private:
// Returned by _send() and _processRemotePacket() to indicate what happened
enum PacketServiceAttemptResult
{
PACKET_SERVICE_ATTEMPT_OK,
PACKET_SERVICE_ATTEMPT_PEER_UNKNOWN,
PACKET_SERVICE_ATTEMPT_SEND_FAILED
};
struct _CBaddPeerFromHello_Data
{
Switch *parent;
Address source;
InetAddress fromAddr;
int localPort;
unsigned int vMajor,vMinor,vRevision;
uint64_t helloPacketId;
uint64_t helloTimestamp;
};
static void _CBaddPeerFromHello(void *arg,const SharedPtr<Peer> &p,Topology::PeerVerifyResult result);
static void _CBaddPeerFromWhois(void *arg,const SharedPtr<Peer> &p,Topology::PeerVerifyResult result); // arg == this
void _propagateMulticast(const SharedPtr<Network> &network,unsigned char *bloom,const MulticastGroup &mg,unsigned int mcHops,unsigned int mcLoadFactor,const MAC &from,unsigned int etherType,const void *data,unsigned int len);
PacketServiceAttemptResult _tryHandleRemotePacket(Demarc::Port localPort,const InetAddress &fromAddr,Packet &packet);
void _doHELLO(Demarc::Port localPort,const InetAddress &fromAddr,Packet &packet);
void _requestWhois(const Address &addr);
Address _sendWhoisRequest(const Address &addr,const Address *peersAlreadyConsulted,unsigned int numPeersAlreadyConsulted);
PacketServiceAttemptResult _trySend(const Packet &packet,bool encrypt);
void _retryPendingFor(const Address &addr);
// Updates entry for crc in multicast history, returns true if already
// present in history and not expired.
inline bool _checkAndUpdateMulticastHistory(const MAC &fromMac,const MAC &toMulticastMac,const void *payload,unsigned int len,const uint64_t nwid,const uint64_t now)
{
uint64_t crc = Utils::crc64(0,fromMac.data,6);
crc = Utils::crc64(crc,toMulticastMac.data,6);
crc = Utils::crc64(crc,payload,len);
crc += nwid; // also include network ID
uint64_t earliest = 0xffffffffffffffffULL;
unsigned long earliestIdx = 0;
for(unsigned int i=0;i<ZT_MULTICAST_DEDUP_HISTORY_LENGTH;++i) {
if (_multicastHistory[i][0] == crc) {
uint64_t then = _multicastHistory[i][1];
_multicastHistory[i][1] = now;
return ((now - then) < ZT_MULTICAST_DEDUP_HISTORY_EXPIRE);
} else if (_multicastHistory[i][1] < earliest) {
earliest = _multicastHistory[i][1];
earliestIdx = i;
}
}
_multicastHistory[earliestIdx][0] = crc; // replace oldest entry
_multicastHistory[earliestIdx][1] = now;
return false;
}
const RuntimeEnvironment *const _r;
// Multicast packet CRC64's for packets we've received recently, to reject
// duplicates during propagation. [0] is CRC64, [1] is time.
uint64_t _multicastHistory[ZT_MULTICAST_DEDUP_HISTORY_LENGTH][2];
struct WhoisRequest
{
uint64_t lastSent;
Address peersConsulted[ZT_MAX_WHOIS_RETRIES]; // by retry
unsigned int retries; // 0..ZT_MAX_WHOIS_RETRIES
};
std::map< Address,WhoisRequest > _outstandingWhoisRequests;
Mutex _outstandingWhoisRequests_m;
struct TXQueueEntry
{
uint64_t creationTime;
Packet packet; // unencrypted/untagged for TX queue
bool encrypt;
};
std::multimap< Address,TXQueueEntry > _txQueue; // by destination address
Mutex _txQueue_m;
struct RXQueueEntry
{
uint64_t creationTime;
Demarc::Port localPort;
Packet packet; // encrypted/tagged
InetAddress fromAddr;
};
std::multimap< Address,RXQueueEntry > _rxQueue; // by source address
Mutex _rxQueue_m;
struct DefragQueueEntry
{
uint64_t creationTime;
Packet frag0;
Packet::Fragment frags[ZT_MAX_PACKET_FRAGMENTS - 1];
unsigned int totalFragments; // 0 if only frag0 received, waiting for frags
uint32_t haveFragments; // bit mask, LSB to MSB
};
std::map< uint64_t,DefragQueueEntry > _defragQueue;
Mutex _defragQueue_m;
std::map< Array< Address,2 >,uint64_t > _lastUniteAttempt; // key is always sorted in ascending order, for set-like behavior
Mutex _lastUniteAttempt_m;
struct RendezvousQueueEntry
{
InetAddress inaddr;
uint64_t fireAtTime;
Demarc::Port localPort;
};
std::map< Address,RendezvousQueueEntry > _rendezvousQueue;
Mutex _rendezvousQueue_m;
};
} // namespace ZeroTier
#endif