/*
* Created on 18 Sep 2007
* Created by Allan Crooks
* Copyright (C) 2007 Aelitis, All Rights Reserved.
*
* 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 2
* 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, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* AELITIS, SAS au capital de 46,603.30 euros
* 8 Allee Lenotre, La Grille Royale, 78600 Le Mesnil le Roi, France.
*/
package com.aelitis.azureus.core.peermanager.messaging.bittorrent.ltep;
import java.util.*;
import org.gudy.azureus2.core3.logging.LogEvent;
import org.gudy.azureus2.core3.logging.LogIDs;
import org.gudy.azureus2.core3.logging.Logger;
import org.gudy.azureus2.core3.util.DirectByteBuffer;
import com.aelitis.azureus.core.networkmanager.NetworkManager;
import com.aelitis.azureus.core.peermanager.messaging.Message;
import com.aelitis.azureus.core.peermanager.messaging.MessageException;
import com.aelitis.azureus.core.peermanager.messaging.MessagingUtil;
import com.aelitis.azureus.core.peermanager.messaging.azureus.AZStylePeerExchange;
import com.aelitis.azureus.core.peermanager.peerdb.PeerItem;
import com.aelitis.azureus.core.peermanager.peerdb.PeerItemFactory;
/**
* @author Allan Crooks
*
* Largely copied from AZPeerExchange.
*/
public class UTPeerExchange implements AZStylePeerExchange, LTMessage {
// Debug flag for testing purposes - currently disabled by default.
public static final boolean ENABLED = true;
private static final LogIDs LOGID = LogIDs.NET;
private static final int IPv4_SIZE_WITH_PORT = 6;
private static final int IPv6_SIZE_WITH_PORT = 18;
private DirectByteBuffer buffer = null;
private String description = null;
private final byte version;
private final PeerItem[] peers_added;
private final PeerItem[] peersAddedNoSeeds;
private final PeerItem[] peers_dropped;
public UTPeerExchange(PeerItem[] _peers_added, PeerItem[] _peers_dropped, PeerItem[] peersAddedNoSeeds, byte version ) {
this.peers_added = _peers_added;
this.peers_dropped = _peers_dropped;
this.version = version;
this.peersAddedNoSeeds = peersAddedNoSeeds != null ? peersAddedNoSeeds : _peers_added;
}
private void insertPeers(String key_name, Map root_map, boolean include_flags, PeerItem[] peers) {
if (peers == null) {return;}
if (peers.length == 0) {return;}
List v4_peers = null;
List v6_peers = null;
for (int i=0; i<peers.length; i++) {
if (!peers[i].isIPv4()) {
if (v6_peers == null) {
v6_peers = new ArrayList();
v4_peers = new ArrayList(Arrays.asList(peers).subList(0, i));
}
v6_peers.add(peers[i]);
}
else {
if (v4_peers != null) {
v4_peers.add(peers[i]);
}
}
}
if (v4_peers == null) {v4_peers = Arrays.asList(peers);}
insertPeers(key_name, root_map, include_flags, v4_peers, IPv4_SIZE_WITH_PORT);
insertPeers(key_name + "6", root_map, include_flags, v6_peers, IPv6_SIZE_WITH_PORT);
}
private void insertPeers(String key_name, Map root_map, boolean include_flags, List peers, int peer_byte_size) {
if (peers == null) {return;}
if (peers.isEmpty()) {return;}
byte[] raw_peers = new byte[peers.size() * peer_byte_size];
byte[] peer_flags = (include_flags) ? new byte[peers.size()] : null;
PeerItem peer;
for (int i=0; i<peers.size(); i++ ) {
peer = (PeerItem)peers.get(i);
byte[] serialised_peer = peer.getSerialization();
if (serialised_peer.length != peer_byte_size) {System.out.println("> " + serialised_peer.length + ":" + peer_byte_size);}
System.arraycopy(serialised_peer, 0, raw_peers, i * peer_byte_size, peer_byte_size);
if (peer_flags != null && NetworkManager.getCryptoRequired(peer.getCryptoLevel())) {
peer_flags[i] |= 0x01; // Encrypted connection.
}
// 0x02 indicates if the peer is a seed, but that's difficult to determine
// so we'll leave it.
} // end for
root_map.put(key_name, raw_peers);
if (peer_flags != null) {
root_map.put(key_name + ".f", peer_flags);
}
}
private List extractPeers(String key_name, Map root_map, int peer_byte_size, boolean noSeeds) {
ArrayList peers = new ArrayList();
byte[] raw_peer_data = (byte[])root_map.get(key_name);
if( raw_peer_data != null ) {
if (raw_peer_data.length % peer_byte_size != 0) {
if (Logger.isEnabled())
Logger.log(new LogEvent(LOGID, LogEvent.LT_WARNING, "PEX (UT): peer data size not multiple of " + peer_byte_size + ": " + raw_peer_data.length));
}
int peer_num = raw_peer_data.length / peer_byte_size;
byte[] flags = null;
if (root_map != null) {
Object flags_obj = root_map.get(key_name + ".f");
// For some reason, some peers send flags as longs. I haven't seen
// it myself, so I don't know how to extract data from it. So we'll
// just stick to byte arrays.
if (flags_obj instanceof byte[]) {flags = (byte[])flags_obj;}
}
if (flags != null && flags.length != peer_num) {
if (flags.length > 0) {
if (Logger.isEnabled()) {
Logger.log(new LogEvent(LOGID, LogEvent.LT_WARNING, "PEX (UT): invalid peer flags: peers=" + peer_num + ", flags=" + flags.length ));
}
}
flags = null;
}
for (int i=0; i<peer_num; i++) {
byte[] full_address = new byte[peer_byte_size];
System.arraycopy(raw_peer_data, i * peer_byte_size, full_address, 0, peer_byte_size);
byte type = PeerItemFactory.HANDSHAKE_TYPE_PLAIN;
if (flags != null && (flags[i] & 0x01) != 0)
type = PeerItemFactory.HANDSHAKE_TYPE_CRYPTO;
if (flags != null && (flags[i] & 0x02) != 0 && noSeeds)
continue;
try {
PeerItem peer = PeerItemFactory.createPeerItem(full_address, PeerItemFactory.PEER_SOURCE_PEER_EXCHANGE, type, 0);
peers.add(peer);
}
catch (Exception e) {
if (Logger.isEnabled())
Logger.log(new LogEvent(LOGID, LogEvent.LT_WARNING, "PEX (UT): invalid peer received"));
}
}
}
return peers;
}
public PeerItem[] getAddedPeers(boolean seeds) {return seeds ? peers_added : peersAddedNoSeeds; }
public PeerItem[] getAddedPeers() { return peers_added; }
public PeerItem[] getDroppedPeers() { return peers_dropped; }
public String getID() { return LTMessage.ID_UT_PEX; }
public byte[] getIDBytes() { return LTMessage.ID_UT_PEX_BYTES; }
public String getFeatureID() { return LTMessage.LT_FEATURE_ID; }
public int getFeatureSubID() { return LTMessage.SUBID_UT_PEX; }
public int getType() { return Message.TYPE_PROTOCOL_PAYLOAD; }
public byte getVersion() { return version; };
public String getDescription() {
if( description == null ) {
int add_count = peers_added == null ? 0 : peers_added.length;
int drop_count = peers_dropped == null ? 0 : peers_dropped.length;
description = getID().toUpperCase() + " with " +add_count+ " added and " +drop_count+ " dropped peers";
}
return description;
}
public DirectByteBuffer[] getData() {
if( buffer == null ) {
Map payload_map = new HashMap();
// bencoded_buffer = payload_map;
insertPeers("added", payload_map, true, peers_added );
insertPeers("dropped", payload_map, false, peers_dropped );
buffer = MessagingUtil.convertPayloadToBencodedByteStream(payload_map, DirectByteBuffer.AL_MSG_UT_PEX);
}
return new DirectByteBuffer[] {buffer};
}
public Message deserialize( DirectByteBuffer data, byte version ) throws MessageException {
Map root = MessagingUtil.convertBencodedByteStreamToPayload(data, 2, getID());
List added = extractPeers("added", root, IPv4_SIZE_WITH_PORT,false);
List addedNoSeeds = extractPeers("added", root, IPv4_SIZE_WITH_PORT,true);
List dropped = extractPeers("dropped", root, IPv4_SIZE_WITH_PORT,false);
added.addAll(extractPeers("added6", root, IPv6_SIZE_WITH_PORT,false));
addedNoSeeds.addAll(extractPeers("added6", root, IPv6_SIZE_WITH_PORT,true));
dropped.addAll(extractPeers("dropped6", root, IPv6_SIZE_WITH_PORT,false));
PeerItem[] addedArr = (PeerItem[])added.toArray(new PeerItem[added.size()]);
PeerItem[] addedNoSeedsArr = (PeerItem[])addedNoSeeds.toArray(new PeerItem[addedNoSeeds.size()]);
PeerItem[] droppedArr = (PeerItem[])dropped.toArray(new PeerItem[dropped.size()]);
return new UTPeerExchange(addedArr, droppedArr,addedNoSeedsArr, version);
}
public void destroy() {
if( buffer != null ) buffer.returnToPool();
}
/**
* Arbitrary value - most clients are configured to about 100 or so...
* We'll allow ourselves to be informed about 200 connected peers from
* the initial handshake, and then cap either list to about 100.
*
* These values are plucked from the air really - although I've seen PEX
* sizes where the added list is about 300 (sometimes), most contain a
* sensible number (not normally over 100).
*
* Subsequent PEX messages are relatively small too, so we'll stick to
* smaller limits - 50 would be probably fine, but watching some big
* swarms over a short period, the biggest "added" list I saw was one
* containing 38 peers, so it's quite possible list sizes above 50 get
* sent out. So 100 is a safe-ish figure.
*
* Update: uTorrent doesn't have any set limits on this, apparently it simply
* depends on the number of connections a peer has, which can be large for
* fast peers (I've seen 350 peers for example). Increased limits somewhat
* and added code to ignore excessive peers rather than dropping the
* connection
*/
public int getMaxAllowedPeersPerVolley(boolean initial, boolean added) {
return (initial && added) ? 500 : 250;
}
/**** DEBUG STUFF ****/
/*
public String toString() {
List adds = (this.peers_added != null) ? Arrays.asList(this.peers_added) : null;
List drops = (this.peers_dropped != null) ? Arrays.asList(this.peers_dropped) : null;
return "UTPEX: " + adds + ", " + drops;
}
private Map bencoded_buffer = null;
public static void main(String[] args) throws Exception {
PeerItem[] p1 = new PeerItem[] {
PeerItemFactory.createPeerItem("2001:0db8:85a3:08d3:1319:8a2e:0370:7334", 4096, PeerItemFactory.PEER_SOURCE_PEER_EXCHANGE, PeerItemFactory.HANDSHAKE_TYPE_PLAIN, 0, PeerItemFactory.CRYPTO_LEVEL_1, 10),
PeerItemFactory.createPeerItem("2001:0db8:0:0:0:8a2e:0370:7334", 128, PeerItemFactory.PEER_SOURCE_PEER_EXCHANGE, PeerItemFactory.HANDSHAKE_TYPE_CRYPTO, 0, PeerItemFactory.CRYPTO_LEVEL_CURRENT, 10),
PeerItemFactory.createPeerItem("1280:0:0:0:0:0:0:7334", 255, PeerItemFactory.PEER_SOURCE_PEER_EXCHANGE, PeerItemFactory.HANDSHAKE_TYPE_PLAIN, 0, PeerItemFactory.CRYPTO_LEVEL_1, 25),
};
PeerItem[] p2 = new PeerItem[] {
PeerItemFactory.createPeerItem("192.168.0.1", 6473, PeerItemFactory.PEER_SOURCE_PEER_EXCHANGE, PeerItemFactory.HANDSHAKE_TYPE_PLAIN, 16, PeerItemFactory.CRYPTO_LEVEL_1, 10),
PeerItemFactory.createPeerItem("127.0.0.1", 128, PeerItemFactory.PEER_SOURCE_PEER_EXCHANGE, PeerItemFactory.HANDSHAKE_TYPE_CRYPTO, 0, PeerItemFactory.CRYPTO_LEVEL_1, 10),
PeerItemFactory.createPeerItem("172.16.0.1", 255, PeerItemFactory.PEER_SOURCE_PEER_EXCHANGE, PeerItemFactory.HANDSHAKE_TYPE_PLAIN, 0, PeerItemFactory.CRYPTO_LEVEL_1, 25),
};
PeerItem[] p3 = new PeerItem[] {
PeerItemFactory.createPeerItem("2001:0db8:85a3:08d3:1319:8a2e:0370:7334", 55, PeerItemFactory.PEER_SOURCE_PEER_EXCHANGE, PeerItemFactory.HANDSHAKE_TYPE_PLAIN, 0, PeerItemFactory.CRYPTO_LEVEL_1, 10),
PeerItemFactory.createPeerItem("127.0.0.1", 128, PeerItemFactory.PEER_SOURCE_PEER_EXCHANGE, PeerItemFactory.HANDSHAKE_TYPE_CRYPTO, 0, PeerItemFactory.CRYPTO_LEVEL_1, 10),
PeerItemFactory.createPeerItem("1280:0:0:0:0:0:0:7334", 255, PeerItemFactory.PEER_SOURCE_PEER_EXCHANGE, PeerItemFactory.HANDSHAKE_TYPE_PLAIN, 0, PeerItemFactory.CRYPTO_LEVEL_1, 25),
};
UTPeerExchange u1 = new UTPeerExchange(p1, p2, (byte)0);
UTPeerExchange u2 = new UTPeerExchange(p2, p3, (byte)0);
UTPeerExchange u3 = new UTPeerExchange(p3, p1, (byte)0);
UTPeerExchange u4 = new UTPeerExchange(new PeerItem[0], p1, (byte)0);
UTPeerExchange u5 = new UTPeerExchange(p1, new PeerItem[0], (byte)0);
u1.getData();
u2.getData();
u3.getData();
u4.getData();
u5.getData();
UTPeerExchange[] uts = new UTPeerExchange[] {null, u1, u2, u3, u4, u5};
for (int i=1; i<6; i++) {
java.util.Iterator itr = uts[i].bencoded_buffer.keySet().iterator();
while (itr.hasNext()) {
String k = (String)itr.next();
byte[] b = (byte[])uts[i].bencoded_buffer.get(k);
System.out.println(k + ": " + org.gudy.azureus2.core3.util.ByteFormatter.encodeString(b));
}
System.out.println('-');
}
System.out.println(u1.deserialize(u1.getData()[0], (byte)0));
System.out.println(u1.deserialize(u2.getData()[0], (byte)0));
System.out.println(u1.deserialize(u3.getData()[0], (byte)0));
System.out.println(u1.deserialize(u4.getData()[0], (byte)0));
System.out.println(u1.deserialize(u5.getData()[0], (byte)0));
}
*/
}