ZeroTierOne/node/EthernetTap.hpp

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/*
* 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_ETHERNETTAP_HPP
#define ZT_ETHERNETTAP_HPP
#include <stdio.h>
#include <stdlib.h>
#include <map>
#include <list>
#include <vector>
#include <set>
#include <string>
#include <queue>
#include <stdexcept>
#include "Constants.hpp"
#include "InetAddress.hpp"
#include "MAC.hpp"
#include "Mutex.hpp"
#include "Condition.hpp"
#include "MulticastGroup.hpp"
#include "Thread.hpp"
#include "Buffer.hpp"
#include "Array.hpp"
#ifdef __WINDOWS__
#include <WinSock2.h>
#include <Windows.h>
#endif
namespace ZeroTier {
class RuntimeEnvironment;
/**
* System ethernet tap device
*/
class EthernetTap
{
public:
/**
* Construct a new TAP device
*
* Handler arguments: arg,from,to,etherType,data
*
* @param renv Runtime environment
* @param tag A tag used to identify persistent taps at the OS layer (e.g. nwid in hex)
* @param mac MAC address of device
* @param mtu MTU of device
* @param desc If non-NULL, a description (not used on all OSes)
* @param handler Handler function to be called when data is received from the tap
* @param arg First argument to handler function
* @throws std::runtime_error Unable to allocate device
*/
EthernetTap(
const RuntimeEnvironment *renv,
const char *tag,
const MAC &mac,
unsigned int mtu,
void (*handler)(void *,const MAC &,const MAC &,unsigned int,const Buffer<4096> &),
void *arg)
throw(std::runtime_error);
/**
* Close tap and shut down thread
*
* This may block for a few seconds while thread exits.
*/
~EthernetTap();
/**
* Perform OS dependent actions on network configuration change detection
*/
void whack();
/**
* Set whether or not DHCP is enabled (disabled by default)
*
* @param dhcp DHCP status
* @return New state of DHCP (may be false even on 'true' if DHCP enable failed)
*/
bool setDhcpEnabled(bool dhcp);
/**
* Set whether or not DHCP6 is enabled (disabled by default)
*
* @param dhcp DHCP6 status
* @return New state of DHCP6 (may be false even on 'true' if DHCP enable failed)
*/
bool setDhcp6Enabled(bool dhcp);
/**
* Set the user display name for this connection
*
* This does nothing on platforms that don't have this concept.
*
* @param dn User display name
*/
void setDisplayName(const char *dn);
/**
* @return MAC address of this interface
*/
inline const MAC &mac() const throw() { return _mac; }
/**
* @return MTU of this interface
*/
inline unsigned int mtu() const throw() { return _mtu; }
/**
* Add an IP to this interface
*
* @param ip IP and netmask (netmask stored in port field)
* @return True if IP added successfully
*/
bool addIP(const InetAddress &ip);
/**
* Remove an IP from this interface
*
* @param ip IP and netmask (netmask stored in port field)
* @return True if IP removed successfully
*/
bool removeIP(const InetAddress &ip);
/**
* @return Set of IP addresses / netmasks
*/
inline std::set<InetAddress> ips() const
{
Mutex::Lock _l(_ips_m);
return _ips;
}
/**
* @return Set of IP addresses / netmasks included any we did not assign, link-local, etc.
*/
std::set<InetAddress> allIps() const;
/**
* Set this tap's IP addresses to exactly this set of IPs
*
* New IPs are created, ones not in this list are removed.
*
* @param ips IP addresses with netmask in port field
*/
inline void setIps(const std::set<InetAddress> &allIps)
{
for(std::set<InetAddress>::iterator i(allIps.begin());i!=allIps.end();++i)
addIP(*i);
std::set<InetAddress> myIps(ips());
for(std::set<InetAddress>::iterator i(myIps.begin());i!=myIps.end();++i) {
if (!allIps.count(*i))
removeIP(*i);
}
}
/**
* Put a frame, making it available to the OS for processing
*
* @param from MAC address from which frame originated
* @param to MAC address of destination (typically MAC of tap itself)
* @param etherType Ethernet protocol ID
* @param data Frame payload
* @param len Length of frame
*/
void put(const MAC &from,const MAC &to,unsigned int etherType,const void *data,unsigned int len);
/**
* @return OS-specific device or connection name
*/
std::string deviceName() const;
/**
* Fill or modify a set to contain multicast groups for this device
*
* This populates a set or, if already populated, modifies it to contain
* only multicast groups in which this device is interested.
*
* This should always include the blind wildcard MulticastGroup (MAC of
* ff:ff:ff:ff:ff:ff and 0 ADI field).
*
* @param groups Set to modify in place
* @return True if set was changed since last call
*/
bool updateMulticastGroups(std::set<MulticastGroup> &groups);
/**
* Thread main method; do not call elsewhere
*/
void threadMain()
throw();
private:
const MAC _mac;
const unsigned int _mtu;
const RuntimeEnvironment *_r;
std::set<InetAddress> _ips;
Mutex _ips_m;
void (*_handler)(void *,const MAC &,const MAC &,unsigned int,const Buffer<4096> &);
void *_arg;
bool _dhcp;
bool _dhcp6;
Thread _thread;
#ifdef __UNIX_LIKE__
char _dev[16];
int _fd;
int _shutdownSignalPipe[2];
#endif
#ifdef __WINDOWS__
HANDLE _tap;
OVERLAPPED _tapOvlRead,_tapOvlWrite;
char _tapReadBuf[ZT_IF_MTU + 32];
HANDLE _injectSemaphore;
GUID _deviceGuid;
std::string _myDeviceInstanceId; // NetCfgInstanceId, a GUID
std::string _myDeviceInstanceIdPath; // DeviceInstanceID, another kind of "instance ID"
std::queue< std::pair< Array<char,ZT_IF_MTU + 32>,unsigned int > > _injectPending;
Mutex _injectPending_m;
volatile bool _run;
#endif
};
} // namespace ZeroTier
#endif