messages.cs

P2P (peer to peer) file sharing program in C#. Supports Gnutella, Gnutella2, eDonkey, and OpenNap. w

				lock(HostCache.recentHubs)
					Sck.scks[root.sockNum].neighbors.Add(new IPEndPoint(Endian.GetIPAddress(root.inPayload, offset), Endian.ToUInt16(root.inPayload, offset+4, root.be)));
			}

			public override Child ChildType(ref string name)
			{
				if(name == "GU")
					return new GuIdent();
				else if(name == "V")
					return new VendorCode();
				else if(name == "LS")
					return new LibraryStats();
				else if(name == "HS")
					return new HubStatus();
				else
					return new UnknownChild(ref name);
			}

			public class GuIdent : Child
			{
				public override void Process(int offset, int len)
				{
					//
				}
			}

			public class VendorCode : Child
			{
				public override void Process(int offset, int len)
				{
					//
				}
			}

			public class LibraryStats : Child
			{
				public override void Process(int offset, int len)
				{
					//
				}
			}

			public class HubStatus : Child
			{
				public override void Process(int offset, int len)
				{
					//
				}
			}
		}

		public class CachedHub : Child
		{
			public IPAddress ipa;
			public ushort port;
			public int timeStamp;

			public override void Process(int offset, int len)
			{
				if(len == 10)
				{
					this.ipa = Endian.GetIPAddress(root.inPayload, offset);
					this.port = Endian.ToUInt16(root.inPayload, offset+4, root.be);
					this.timeStamp = Endian.ToInt32(root.inPayload, offset+len-4, root.be);
				}
				else
					Utils.Diag("G2 KHL/CH wrong length: " + len.ToString());
			}

			public override Child ChildType(ref string name)
			{
				if(name == "GU")
					return new GuIdent();
				else if(name == "V")
					return new VendorCode();
				else if(name == "LS")
					return new LibraryStats();
				else if(name == "HS")
					return new HubStatus();
				else
					return new UnknownChild(ref name);
			}

			public class GuIdent : Child
			{
				public override void Process(int offset, int len)
				{
					//
				}
			}

			public class VendorCode : Child
			{
				public override void Process(int offset, int len)
				{
					//
				}
			}

			public class LibraryStats : Child
			{
				public override void Process(int offset, int len)
				{
					//
				}
			}

			public class HubStatus : Child
			{
				public override void Process(int offset, int len)
				{
					//
				}
			}
		}
	}

	public class Push : Message
	{
		public int offsetGUID = -1;

		public override void Process(int offset, int len)
		{
			Child child = this.children;
			while(child != null)
			{
				child.Read(child.offset);
				child = child.nextChild;
			}
			if(offsetGUID != -1)
			{
				if(GUID.Compare(root.inPayload, offsetGUID, Stats.settings.myGUID, 0))
				{
					//this push was for us
					goto push_for_us;
				}
				else if(Stats.Updated.Gnutella2.ultrapeer)
				{
					//maybe we can route this push
					GUIDitem gitem = new GUIDitem(root.inPayload, offsetGUID);
					Router.RouteEntry re;
					lock(Router.htRoutes)
					{
						if(Router.htRoutes.ContainsKey(gitem))
							re = (Router.RouteEntry)Router.htRoutes[gitem];
#if	DEBUG
						else
						{
							Utils.Diag("G2 Push no route found");
							return;
						}
#else
						else
							return;
#endif
					}
					OCopy ocopy = new OCopy();
					ocopy.payload = root.inPayload;
					ocopy.CreateHeader("PUSH", root.be, root.cf);
					Router.RoutePacket(ocopy, re);
				}
			}
			if(this.children == null)
				goto push_for_us;

			return;

		push_for_us:
			if(len == 6)
			{
				IPAddress ipa = Endian.GetIPAddress(root.inPayload, offset);
				int port = Endian.ToUInt16(root.inPayload, offset+4, root.be);
				//the -5 indicates it's a G2, not G1 upload
				UploadManager.Outgoing(-5, ipa.ToString(), port);
			}
		}

		public override Child ChildType(ref string name)
		{
			if(name == "TO")
				return new To();
			else
				return new UnknownChild(ref name);
		}

		public class To : Child
		{
			public override void Process(int offset, int len)
			{
				if(len == 16)
					((Push)this.root).offsetGUID = offset;
				else
					System.Diagnostics.Debug.WriteLine("g2 Push guid is of wrong length: " + len.ToString());
			}
		}
	}

	public class QueryHashTable : Message
	{
		public override void Process(int offset, int len)
		{
			if(root.inPayload[offset] == 0x00)
			{
				lock(Sck.scks[root.sockNum])
				{
					if(len != 6)
						System.Diagnostics.Debug.WriteLine("g2 qht wrong size: " + len.ToString());
					Sck.scks[root.sockNum].inQHT = new BitArray(Endian.ToInt32(root.inPayload, offset+1, root.be), true);
				}
			}
			else if(root.inPayload[offset] == 0x01)
			{
				lock(Sck.scks[root.sockNum])
				{
					//first fragment?
					if(root.inPayload[offset+1] == 0x01)
					{
						Sck.scks[root.sockNum].inRawQHTindex = 0;
						Sck.scks[root.sockNum].inRawQHT = new byte[(len-5) * (int)root.inPayload[offset+2]];
					}
					Array.Copy(root.inPayload, offset+5, Sck.scks[root.sockNum].inRawQHT, Sck.scks[root.sockNum].inRawQHTindex, len-5);
					Sck.scks[root.sockNum].inRawQHTindex += (len-5);
					//last fragment?
					if(root.inPayload[offset+1] == root.inPayload[offset+2])
					{
						BitArray baPatch;
						bool compressed = (root.inPayload[offset+3] == 0x01);
						if(!compressed)
							baPatch = new BitArray(Sck.scks[root.sockNum].inRawQHT);
						else
						{
							byte[] unCompressed = new byte[Sck.scks[root.sockNum].inQHT.Length / 8];
							ICSharpCode.SharpZipLib.Zip.Compression.Inflater ifer = new ICSharpCode.SharpZipLib.Zip.Compression.Inflater();
							ifer.SetInput(Sck.scks[root.sockNum].inRawQHT, 0, Sck.scks[root.sockNum].inRawQHTindex);
							ifer.Inflate(unCompressed);
							baPatch = new BitArray(unCompressed);
						}
						//apply the patch
						Sck.scks[root.sockNum].inQHT.Xor(baPatch);
					}
				}
			}
			else
				System.Diagnostics.Debug.WriteLine("q2 qht wrong command: " + root.inPayload[offset].ToString());
		}
	}

	public class QueryKeyRequest : Message
	{
		public override void Process(int offset, int len)
		{
			if(root.sockNum != -1)
			{
				System.Diagnostics.Debug.WriteLine("g2 qkr over tcp?");
				return;
			}
			if(!Stats.Updated.Gnutella2.ultrapeer)
				return;
			Child child = this.children;
			while(child != null)
			{
				child.Read(child.offset);
				child = child.nextChild;
			}
		}

		public override Child ChildType(ref string name)
		{
			if(name == "RNA")
				return new RNodeAddress();
			else
				return new UnknownChild(ref name);
		}

		public class RNodeAddress : Child
		{
			public override void Process(int offset, int len)
			{
				if(len == 6)
				{
					IPEndPoint ipep = new IPEndPoint(Endian.GetIPAddress(root.inPayload, offset), Endian.ToUInt16(root.inPayload, offset+4, root.be));
					OQKA oqka = new OQKA();
					oqka.queryKey = GUID.rand.Next();
					oqka.qk = true;
					oqka.sna = ipep.Address;
					HostCache.SentQueryKey(oqka.queryKey, ipep);
					UDPSR.SendOutgoingPacket(oqka, ipep);
				}
				else
					System.Diagnostics.Debug.WriteLine("RNodeAddress invalid len: " + len.ToString());
			}
		}
	}

	public class QueryKeyAnswer : Message
	{
		public int queryKey = -1;
		public bool qk = false;
		public IPAddress sna = null;
		public IPAddress qna = null;

		public override void Process(int offset, int len)
		{
			Child child = this.children;
			while(child != null)
			{
				child.Read(child.offset);
				child = child.nextChild;
			}
			try
			{
				if(!qk)
				{
#if DEBUG
					System.Diagnostics.Debug.WriteLine("g2 no query key received... perhaps our query key is no longer valid");
#endif
					HubInfo hi;
					lock(HostCache.hubCache)
					{
						if(qna == null)
							hi = (HubInfo)HostCache.hubCache[root.ipep.Address];
						else
							hi = (HubInfo)HostCache.hubCache[qna];
					}
					hi.timeKnown = 0;
					hi.mhi.qk = false;
					hi.mhi.queryKeyedHub = null;
				}
				else
				{
					//System.Diagnostics.Debug.WriteLine("query key present");
					HubInfo hi;
					lock(HostCache.hubCache)
					{
						if(qna == null)
						{
							hi = (HubInfo)HostCache.hubCache[root.ipep.Address];
							hi.mhi.queryKeyedHub = null;
						}
						else
						{
							hi = (HubInfo)HostCache.hubCache[qna];
							hi.mhi.queryKeyedHub = Sck.scks[root.sockNum].remoteIPA;
						}
					}
					hi.timeKnown = 0;
					hi.mhi.queryKey = this.queryKey;
					hi.mhi.qk = true;
					//we need to use this hub for either a normal query or a requery from a download
					int chance;
					int val = 1;
					if(ReQuery.g2requeried)
					{
						val = 2;
						ReQuery.g2requeried = false;
					}
					chance = GUID.rand.Next(0, val);
					if(chance == 1 || (Search.activeSearches.Count == 0 && val == 2))
					{
						if(qna == null)
							ReQuery.Gnutella2NewHub(root.ipep.Address, hi);
						else
							ReQuery.Gnutella2NewHub(qna, hi);
					}
					else if(chance == 0)
					{
						lock(Search.activeSearches)
						{
							if(Search.activeSearches.Count > 0)
							{
								int which = GUID.rand.Next(0, Search.activeSearches.Count);
								if(qna == null)
									((Search)Search.activeSearches[which]).NewHub(root.ipep.Address, hi);
								else
									((Search)Search.activeSearches[which]).NewHub(qna, hi);
							}
						}
					}
				}
			}
			catch(Exception e)
			{
				System.Diagnostics.Debug.WriteLine("g2 QKA: " + e.Message);
				System.Diagnostics.Debug.WriteLine(e.StackTrace);
			}
			try
			{
				//routing?
				if(Stats.Updated.Gnutella2.ultrapeer && !this.sna.Equals(Stats.Updated.myIPA) && this.qna == null)
				{
					lock(HostCache.recentHubs)
					{
						if(ConnectionManager.htDirects.ContainsKey(this.sna))
						{
							int sockNum = ((ConnectionManager.G2Host)ConnectionManager.htDirects[this.sna]).sockNum;
							OQKA oqka = new OQKA();
							oqka.qna = root.ipep.Address;
							oqka.sna = this.sna;
							oqka.queryKey = this.queryKey;
							oqka.qk = this.qk;
							Sck.scks[sockNum].SendPacket(oqka);
						}
					}
				}
			}
			catch(Exception e)
			{
				System.Diagnostics.Debug.WriteLine("g2 QKA2: " + e.Message);
				System.Diagnostics.Debug.WriteLine(e.StackTrace);
			}
		}

		public override Child ChildType(ref string name)
		{
			if(name == "QK")
				return new QueryKey();
			else if(name == "SNA")
				return new SNodeAddress();
			else if(name == "QNA")
				return new QNodeAddress();
			else
				return new UnknownChild(ref name);
		}

		public class QueryKey : Child
		{
			public override void Process(int offset, int len)
			{
				if(len >= 4)
				{
					((QueryKeyAnswer)this.root).queryKey = Endian.ToInt32(root.inPayload, offset, root.be);
					((QueryKeyAnswer)this.root).qk = true;
				}
			}
		}

		public class SNodeAddress : Child
		{
			public override void Process(int offset, int len)
			{
				if(len == 4 || len == 6)
					((QueryKeyAnswer)this.root).sna = Endian.GetIPAddress(root.inPayload, offset);
				else
					Utils.Diag("QKA SNA wrong size");
			}
		}

		public class QNodeAddress : Child
		{
			public override void Process(int offset, int len)
			{
				if(len == 4 || len == 6)
					((QueryKeyAnswer)this.root).qna = Endian.GetIPAddress(root.inPayload, offset);
				else
					Utils.Diag("QKA QNA wrong size");
			}
		}
	}

	public class Query : Message
	{
		//descriptive name
		public string dn = "";
		//udp or tcp
		public bool fromUdp = false;
		//return address and query key
		public IPEndPoint ipepReturn = null;
		public int queryKey;
		//urn linked list
		public URNinfo urns = null;
		public class URNinfo
		{
			/// <summary>
			/// range in root.inPayload... not this.fullurn
			/// </summary>
			public int loc, len;
			//full urn in string form (ex. urn:sha1:WIXYJFVJMIWNMUWPRPBGUTODIV52RMJA)
			public string fullurn;
			//next URNinfo object
			public URNinfo next = null;
		}
		//size restrictions:
		public bool sizeRestrict = false;
		public uint minSize;
		public uint maxSize;
		//interests; null means everything
		public string[] interests = null;

		public override void Process(int offset, int len)
		{
			if(len != 16)
			{
				System.Diagnostics.Debug.WriteLine("bad g2 query payload length: " + len.ToString());
				throw new Exception("bad g2 query payload length");
			}
			if(root.ipep != null)
				this.fromUdp = true;

			//whether or not we're an ultrapeer, it's necessary to make sure this isn't a duplicate query
			GUIDitem gitem = new GUIDitem(root.inPayload, offset);
			Router.RouteEntry re;
			lock(Router.htRoutes)
			{
				//query duplicate?
				if(Router.htRoutes.ContainsKey(gitem))
					return;
				re = new Router.RouteEntry();
				re.gitem_key = gitem;
				if(this.fromUdp)
				{
					//this may change if a udp child is found
					re.ipep = root.ipep;
					re.sckNum = -1;
				}
				else
				{
					re.ipep = null;
					re.sckNum = root.sockNum;
				}
				re.timeLeft = 120;
				Router.htRoutes.Add(gitem, re);
			}

			Child child = this.children;
			while(child != null)
			{
				child.Read(child.offset);
				child = child.nextChild;
			}

			//honor udp packet if present
			if(this.ipepReturn != null)
			{
				re.ipep = this.ipepReturn;
				re.sckNum = -1;
			}

			//check query key
			bool sendACK = false;
			if(Stats.Updated.Gnutella2.ultrapeer && this.ipepReturn != null && this.fromUdp)
			{
				if(!HostCache.QueryKeyOK(this.ipepReturn, this.queryKey))
				{
#if DEBUG
	Utils.Diag("someone's g2 key wasn't valid");
#endif
					//we need to notify the host that the query key is invalid
					OQKA oqka = new OQKA();
					oqka.sna = this.ipep.Address;
					oqka.qk = false;
					oqka.qna = null;
					UDPSR.SendOutgoingPacket(oqka, this.ipepReturn);
					return;
				}
				else
					sendACK = true;
			}
			if(Stats.Updated.Gnutella2.ultrapeer && !this.fromUdp)
				if(Sck.scks[this.sockNum].mode == G2Mode.Leaf)
					sendACK = true;
			if(sendACK)
			{
				//send qa either by udp or tcp
				OQA oqa = new OQA();
				oqa.sGUID = root.inPayload;
				oqa.gOffset = offset;
				oqa.tcp = (this.sockNum != -1);
				if(oqa.tcp)
					Sck.scks[this.sockNum].SendPacket(oqa);
				else
				{
					if(this.ipepReturn != null)