ZeroTierOne/node/Multicaster.hpp
2024-09-26 08:52:29 -04:00

221 lines
6.7 KiB
C++

/*
* Copyright (c)2019 ZeroTier, Inc.
*
* Use of this software is governed by the Business Source License included
* in the LICENSE.TXT file in the project's root directory.
*
* Change Date: 2026-01-01
*
* On the date above, in accordance with the Business Source License, use
* of this software will be governed by version 2.0 of the Apache License.
*/
/****/
#ifndef ZT_MULTICASTER_HPP
#define ZT_MULTICASTER_HPP
#include "Address.hpp"
#include "Constants.hpp"
#include "Hashtable.hpp"
#include "MAC.hpp"
#include "MulticastGroup.hpp"
#include "Mutex.hpp"
#include "OutboundMulticast.hpp"
#include "SharedPtr.hpp"
#include "Utils.hpp"
#include <list>
#include <map>
#include <stdint.h>
#include <string.h>
#include <vector>
namespace ZeroTier {
class RuntimeEnvironment;
class CertificateOfMembership;
class Packet;
class Network;
/**
* Database of known multicast peers within a network
*/
class Multicaster {
public:
Multicaster(const RuntimeEnvironment* renv);
~Multicaster();
/**
* Add or update a member in a multicast group
*
* @param now Current time
* @param nwid Network ID
* @param mg Multicast group
* @param member New member address
*/
inline void add(void* tPtr, int64_t now, uint64_t nwid, const MulticastGroup& mg, const Address& member)
{
Mutex::Lock _l(_groups_m);
_add(tPtr, now, nwid, mg, _groups[Multicaster::Key(nwid, mg)], member);
}
/**
* Add multiple addresses from a binary array of 5-byte address fields
*
* It's up to the caller to check bounds on the array before calling this.
*
* @param tPtr Thread pointer to be handed through to any callbacks called as a result of this call
* @param now Current time
* @param nwid Network ID
* @param mg Multicast group
* @param addresses Raw binary addresses in big-endian format, as a series of 5-byte fields
* @param count Number of addresses
* @param totalKnown Total number of known addresses as reported by peer
*/
void addMultiple(void* tPtr, int64_t now, uint64_t nwid, const MulticastGroup& mg, const void* addresses, unsigned int count, unsigned int totalKnown);
/**
* Remove a multicast group member (if present)
*
* @param nwid Network ID
* @param mg Multicast group
* @param member Member to unsubscribe
*/
void remove(uint64_t nwid, const MulticastGroup& mg, const Address& member);
/**
* Append gather results to a packet by choosing registered multicast recipients at random
*
* This appends the following fields to the packet:
* <[4] 32-bit total number of known members in this multicast group>
* <[2] 16-bit number of members enumerated in this packet>
* <[...] series of 5-byte ZeroTier addresses of enumerated members>
*
* If zero is returned, the first two fields will still have been appended.
*
* @param queryingPeer Peer asking for gather (to skip in results)
* @param nwid Network ID
* @param mg Multicast group
* @param appendTo Packet to append to
* @param limit Maximum number of 5-byte addresses to append
* @return Number of addresses appended
* @throws std::out_of_range Buffer overflow writing to packet
*/
unsigned int gather(const Address& queryingPeer, uint64_t nwid, const MulticastGroup& mg, Buffer<ZT_PROTO_MAX_PACKET_LENGTH>& appendTo, unsigned int limit) const;
/**
* Get subscribers to a multicast group
*
* @param nwid Network ID
* @param mg Multicast group
*/
std::vector<Address> getMembers(uint64_t nwid, const MulticastGroup& mg, unsigned int limit) const;
/**
* Send a multicast
*
* @param tPtr Thread pointer to be handed through to any callbacks called as a result of this call
* @param now Current time
* @param network Network
* @param origin Origin of multicast (to not return to sender) or NULL if none
* @param mg Multicast group
* @param src Source Ethernet MAC address or NULL to skip in packet and compute from ZT address (non-bridged mode)
* @param etherType Ethernet frame type
* @param data Packet data
* @param len Length of packet data
*/
void send(void* tPtr, int64_t now, const SharedPtr<Network>& network, const Address& origin, const MulticastGroup& mg, const MAC& src, unsigned int etherType, const void* data, unsigned int len);
/**
* Clean database
*
* @param RR Runtime environment
* @param now Current time
*/
void clean(int64_t now);
private:
struct Key {
Key() : nwid(0), mg()
{
}
Key(uint64_t n, const MulticastGroup& g) : nwid(n), mg(g)
{
}
uint64_t nwid;
MulticastGroup mg;
inline bool operator==(const Key& k) const
{
return ((nwid == k.nwid) && (mg == k.mg));
}
inline bool operator!=(const Key& k) const
{
return ((nwid != k.nwid) || (mg != k.mg));
}
inline unsigned long hashCode() const
{
return (mg.hashCode() ^ (unsigned long)(nwid ^ (nwid >> 32)));
}
};
struct MulticastGroupMember {
MulticastGroupMember()
{
}
MulticastGroupMember(const Address& a, uint64_t ts) : address(a), timestamp(ts)
{
}
inline bool operator<(const MulticastGroupMember& a) const
{
return (address < a.address);
}
inline bool operator==(const MulticastGroupMember& a) const
{
return (address == a.address);
}
inline bool operator!=(const MulticastGroupMember& a) const
{
return (address != a.address);
}
inline bool operator<(const Address& a) const
{
return (address < a);
}
inline bool operator==(const Address& a) const
{
return (address == a);
}
inline bool operator!=(const Address& a) const
{
return (address != a);
}
Address address;
int64_t timestamp; // time of last notification
};
struct MulticastGroupStatus {
MulticastGroupStatus() : lastExplicitGather(0)
{
}
int64_t lastExplicitGather;
std::list<OutboundMulticast> txQueue; // pending outbound multicasts
std::vector<MulticastGroupMember> members; // members of this group
};
void _add(void* tPtr, int64_t now, uint64_t nwid, const MulticastGroup& mg, MulticastGroupStatus& gs, const Address& member);
const RuntimeEnvironment* const RR;
Hashtable<Multicaster::Key, MulticastGroupStatus> _groups;
Mutex _groups_m;
};
} // namespace ZeroTier
#endif