Yet more WIP on mulitcast algo...

node/OutboundMulticast.hpp

@@ -0,0 +1,125 @@
+/*
+ * ZeroTier One - Global Peer to Peer Ethernet
+ * Copyright (C) 2011-2014  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_OUTBOUNDMULTICAST_HPP
+#define ZT_OUTBOUNDMULTICAST_HPP
+
+#include <stdint.h>
+
+#include <vector>
+#include <algorithm>
+
+#include "Constants.hpp"
+#include "MAC.hpp"
+#include "MulticastGroup.hpp"
+#include "Address.hpp"
+#include "Packet.hpp"
+#include "Switch.hpp"
+
+namespace ZeroTier {
+
+/**
+ * An outbound multicast packet
+ *
+ * This object isn't guarded by a mutex; caller must synchronize access.
+ */
+class OutboundMulticast
+{
+public:
+	/**
+	 * Initialize outbound multicast
+	 *
+	 * @param timestamp Creation time
+	 * @param self My ZeroTier address
+	 * @param nwid Network ID
+	 * @param src Source MAC address of frame
+	 * @param dest Destination multicast group (MAC + ADI)
+	 * @param etherType 16-bit Ethernet type ID
+	 * @param payload Data
+	 * @param len Length of data
+	 * @throws std::out_of_range Data too large to fit in a MULTICAST_FRAME
+	 */
+	OutboundMulticast(uint64_t timestamp,const Address &self,uint64_t nwid,const MAC &src,const MulticastGroup &dest,unsigned int etherType,const void *payload,unsigned int len) :
+		_timestamp(timestamp),
+		_nwid(nwid),
+		_source(src),
+		_destination(dest),
+		_etherType(etherType)
+	{
+		_packet.setSource(self);
+		_packet.setVerb(Packet::VERB_MULTICAST_FRAME);
+		_packet.append((char)0);
+		_packet.append((uint32_t)dest.adi());
+		dest.mac().appendTo(_packet);
+		src.appendTo(_packet);
+		_packet.append((uint16_t)etherType);
+		_packet.append(payload,len);
+		_packet.compress();
+	}
+
+	/**
+	 * @return Multicast creation time
+	 */
+	inline uint64_t timestamp() const throw() { return _timestamp; }
+
+	/**
+	 * @return Number of unique recipients to which this packet has already been sent
+	 */
+	inline unsigned int sendCount() const throw() { return (unsigned int)_alreadySentTo.size(); }
+
+	/**
+	 * Try to send this to a given peer if it hasn't been sent to them already
+	 *
+	 * @param sw Switch instance to send packets
+	 * @param toAddr Destination address
+	 * @return True if address is new and packet was sent to switch, false if duplicate
+	 */
+	inline bool send(Switch &sw,const Address &toAddr)
+	{
+		// If things get really big, we can go to a sorted vector or a flat_set implementation
+		for(std::vector<Address>::iterator a(_alreadySentTo.begin());a!=_alreadySentTo.end();++a) {
+			if (*a == toAddr)
+				return false;
+		}
+		_alreadySentTo.push_back(toAddr);
+		sw.send(Packet(_packet,toAddr),true);
+		return true;
+	}
+
+private:
+	uint64_t _timestamp;
+	uint64_t _nwid;
+	MAC _source;
+	MulticastGroup _destination;
+	unsigned int _etherType;
+	Packet _packet; // packet contains basic structure of MULTICAST_FRAME and payload, is re-used with new IV and addressing each time
+	std::vector<Address> _alreadySentTo;
+};
+
+} // namespace ZeroTier
+
+#endif