private bool ProcessPacket(byte[] buffer, int offset, int size, uint opcode, uint nIP, ushort nUDPPort)
{
try
{
MuleApplication.Instance.Statistics.AddDownDataOverheadServer((uint)size);
ED2KServer pServer = MuleApplication.Instance.ServerList.GetServerByIPUDP(nIP, nUDPPort, true);
if (pServer != null)
{
pServer.ResetFailedCount();
}
switch ((OperationCodeEnum)opcode)
{
case OperationCodeEnum.OP_GLOBSEARCHRES:
{
SafeMemFile data = MpdObjectManager.CreateSafeMemFile(buffer, size);
// process all search result packets
int iLeft;
do
{
uint uResultCount = MuleApplication.Instance.SearchList.ProcessUDPSearchAnswer(data, true /*pServer.GetUnicodeSupport()*/, nIP, nUDPPort - 4);
// check if there is another source packet
iLeft = (int)(data.Length - data.Position);
if (iLeft >= 2)
{
byte protocol = data.ReadUInt8();
iLeft--;
if (protocol != MuleConstants.PROTOCOL_EDONKEYPROT)
{
data.Seek(-1, System.IO.SeekOrigin.Current);
iLeft += 1;
break;
}
byte opcode1 = data.ReadUInt8();
iLeft--;
if (opcode1 != (byte)OperationCodeEnum.OP_GLOBSEARCHRES)
{
data.Seek(-2, System.IO.SeekOrigin.Current);
iLeft += 2;
break;
}
}
}while (iLeft > 0);
break;
}
case OperationCodeEnum.OP_GLOBFOUNDSOURCES:
{
SafeMemFile data = MpdObjectManager.CreateSafeMemFile(buffer, size);
// process all source packets
int iLeft;
do
{
byte[] fileid = new byte[16];
data.ReadHash16(fileid);
PartFile file = MuleApplication.Instance.DownloadQueue.GetFileByID(fileid);
if (file != null)
{
file.AddSources(data, nIP, (ushort)(nUDPPort - 4), false);
}
else
{
// skip sources for that file
uint count = data.ReadUInt8();
data.Seek(count * (4 + 2), System.IO.SeekOrigin.Current);
}
// check if there is another source packet
iLeft = (int)(data.Length - data.Position);
if (iLeft >= 2)
{
byte protocol = data.ReadUInt8();
iLeft--;
if (protocol != MuleConstants.PROTOCOL_EDONKEYPROT)
{
data.Seek(-1, System.IO.SeekOrigin.Current);
iLeft += 1;
break;
}
byte opcode1 = data.ReadUInt8();
iLeft--;
if (opcode1 != (byte)OperationCodeEnum.OP_GLOBFOUNDSOURCES)
{
data.Seek(-2, System.IO.SeekOrigin.Current);
iLeft += 2;
break;
}
}
}while (iLeft > 0);
break;
}
case OperationCodeEnum.OP_GLOBSERVSTATRES:
{
if (size < 12 || pServer == null)
{
return(true);
}
uint challenge = BitConverter.ToUInt32(buffer, 0);
if (challenge != pServer.Challenge)
{
return(true);
}
if (pServer != null)
{
pServer.Challenge = 0;
pServer.CryptPingReplyPending = false;
uint tNow = MpdUtilities.Time();
Random rand = new Random();
// if we used Obfuscated ping, we still need to reset the time properly
pServer.LastPingedTime =
Convert.ToUInt32(tNow - (rand.Next() % MuleConstants.ONE_HOUR_SEC));
}
uint cur_user = BitConverter.ToUInt32(buffer, 4);
uint cur_files = BitConverter.ToUInt32(buffer, 8);
uint cur_maxusers = 0;
uint cur_softfiles = 0;
uint cur_hardfiles = 0;
uint uUDPFlags = 0;
uint uLowIDUsers = 0;
uint dwServerUDPKey = 0;
ushort nTCPObfuscationPort = 0;
ushort nUDPObfuscationPort = 0;
if (size >= 16)
{
cur_maxusers = BitConverter.ToUInt32(buffer, 12);
}
if (size >= 24)
{
cur_softfiles = BitConverter.ToUInt32(buffer, 16);
cur_hardfiles = BitConverter.ToUInt32(buffer, 20);
}
if (size >= 28)
{
uUDPFlags = BitConverter.ToUInt32(buffer, 24);
}
if (size >= 32)
{
uLowIDUsers = BitConverter.ToUInt32(buffer, 28);
}
if (size >= 40)
{
// TODO debug check if this packet was encrypted if it has a key
nUDPObfuscationPort = BitConverter.ToUInt16(buffer, 32);
nTCPObfuscationPort = BitConverter.ToUInt16(buffer, 34);;
dwServerUDPKey = BitConverter.ToUInt32(buffer, 36);
}
if (pServer != null)
{
pServer.Ping = MpdUtilities.GetTickCount() - pServer.LastPinged;
pServer.UserCount = cur_user;
pServer.FileCount = cur_files;
pServer.MaxUsers = cur_maxusers;
pServer.SoftFiles = cur_softfiles;
pServer.HardFiles = cur_hardfiles;
pServer.ServerKeyUDP = dwServerUDPKey;
pServer.ObfuscationPortTCP = nTCPObfuscationPort;
pServer.ObfuscationPortUDP = nUDPObfuscationPort;
// if the received UDP flags do not match any already stored UDP flags,
// reset the server version string because the version (which was determined by last connecting to
// that server) is most likely not accurat any longer.
// this may also give 'false' results because we don't know the UDP flags when connecting to a server
// with TCP.
//if (pServer.GetUDPFlags() != uUDPFlags)
// pServer.Version(_T = "");
pServer.UDPFlags = (ED2KServerUdpFlagsEnum)uUDPFlags;
pServer.LowIDUsers = uLowIDUsers;
pServer.SetLastDescPingedCount(false);
if (pServer.LastDescPingedCount < 2)
{
// eserver 16.45+ supports a new OP_SERVER_DESC_RES answer, if the OP_SERVER_DESC_REQ contains a uint
// challenge, the server returns additional info with OP_SERVER_DESC_RES. To properly distinguish the
// old and new OP_SERVER_DESC_RES answer, the challenge has to be selected carefully. The first 2 bytes
// of the challenge (in network byte order) MUST NOT be a valid string-len-int16!
Packet packet1 =
MuleApplication.Instance.NetworkObjectManager.CreatePacket(OperationCodeEnum.OP_SERVER_DESC_REQ, 4);
uint uDescReqChallenge =
((uint)MpdUtilities.GetRandomUInt16() << 16) +
MuleConstants.INV_SERV_DESC_LEN; // 0xF0FF = an 'invalid' string length.
pServer.DescReqChallenge = uDescReqChallenge;
Array.Copy(BitConverter.GetBytes(uDescReqChallenge), packet1.Buffer, 4);
MuleApplication.Instance.Statistics.AddUpDataOverheadServer(packet1.Size);
MuleApplication.Instance.ServerConnect.SendUDPPacket(packet1, pServer, true);
}
else
{
pServer.SetLastDescPingedCount(true);
}
}
break;
}
case OperationCodeEnum.OP_SERVER_DESC_RES:
{
if (pServer == null)
{
return(true);
}
// old packet: <name_len 2><name name_len><desc_len 2 desc_en>
// new packet: <challenge 4><taglist>
//
// NOTE: To properly distinguish between the two packets which are both useing the same opcode...
// the first two bytes of <challenge> (in network byte order) have to be an invalid <name_len> at least.
SafeMemFile srvinfo = MpdObjectManager.CreateSafeMemFile(buffer, size);
if (size >= 8 && BitConverter.ToUInt16(buffer, 0) == MuleConstants.INV_SERV_DESC_LEN)
{
if (pServer.DescReqChallenge != 0 && BitConverter.ToUInt32(buffer, 0) == pServer.DescReqChallenge)
{
pServer.DescReqChallenge = 0;
srvinfo.ReadUInt32(); // skip challenge
uint uTags = srvinfo.ReadUInt32();
for (uint i = 0; i < uTags; i++)
{
Tag tag = MpdObjectManager.CreateTag(srvinfo, true /*pServer.GetUnicodeSupport()*/);
if (tag.NameID == MuleConstants.ST_SERVERNAME && tag.IsStr)
{
pServer.ServerName = tag.Str;
}
else if (tag.NameID == MuleConstants.ST_DESCRIPTION && tag.IsStr)
{
pServer.Description = tag.Str;
}
else if (tag.NameID == MuleConstants.ST_DYNIP && tag.IsStr)
{
// Verify that we really received a DN.
IPAddress address;
if (!IPAddress.TryParse(tag.Str, out address) ||
address == IPAddress.None)
{
string strOldDynIP = pServer.DynIP;
pServer.DynIP = tag.Str;
// If a dynIP-server changed its address or, if this is the
// first time we get the dynIP-address for a server which we
// already have as non-dynIP in our list, we need to remove
// an already available server with the same 'dynIP:port'.
if (string.Compare(strOldDynIP, pServer.DynIP, true) != 0)
{
MuleApplication.Instance.ServerList.RemoveDuplicatesByAddress(pServer);
}
}
}
else if (tag.NameID == MuleConstants.ST_VERSION && tag.IsStr)
{
pServer.Version = tag.Str;
}
else if (tag.NameID == MuleConstants.ST_VERSION && tag.IsInt)
{
pServer.Version =
string.Format("{0}.{1}", tag.Int >> 16, tag.Int & 0xFFFF);
}
}
}
else
{
// A server sent us a new server description packet (including a challenge) although we did not
// ask for it. This may happen, if there are multiple servers running on the same machine with
// multiple IPs. If such a server is asked for a description, the server will answer 2 times,
// but with the same IP.
}
}
else
{
string strName = srvinfo.ReadString(true /*pServer.GetUnicodeSupport()*/);
string strDesc = srvinfo.ReadString(true /*pServer.GetUnicodeSupport()*/);
pServer.Description = strDesc;
pServer.ServerName = strName;
}
break;
}
default:
return(false);
}
return(true);
}
catch (Exception error)
{
ProcessPacketError((uint)size, (uint)opcode, nIP, nUDPPort, error);
if (opcode == (byte)OperationCodeEnum.OP_GLOBSEARCHRES ||
opcode == (byte)OperationCodeEnum.OP_GLOBFOUNDSOURCES)
{
return(true);
}
}
return(false);
}
private bool ProcessPacket(byte[] packet, uint offset, uint size,
byte opcode, uint ip, ushort port)
{
switch ((OperationCodeEnum)opcode)
{
case OperationCodeEnum.OP_REASKCALLBACKUDP:
{
MuleApplication.Instance.Statistics.AddDownDataOverheadOther(size);
UpDownClient buddy = MuleApplication.Instance.ClientList.Buddy;
if (buddy != null)
{
if (size < 17 || buddy.ClientSocket == null)
{
break;
}
if (MpdUtilities.Md4Cmp(packet, (int)offset, buddy.BuddyID, 0) == 0)
{
Array.Copy(BitConverter.GetBytes(ip), 0,
packet, offset + 10, 4);
Array.Copy(BitConverter.GetBytes(port), 0,
packet, offset + 14, 2);
Packet response =
MuleApplication.Instance.NetworkObjectManager.CreatePacket(MuleConstants.PROTOCOL_EMULEPROT);
response.OperationCode = OperationCodeEnum.OP_REASKCALLBACKTCP;
response.Buffer = new byte[size];
Array.Copy(packet, offset + 10, response.Buffer, 0, size - 10);
response.Size = size - 10;
MuleApplication.Instance.Statistics.AddUpDataOverheadFileRequest(response.Size);
buddy.SendPacket(response, true);
}
}
break;
}
case OperationCodeEnum.OP_REASKFILEPING:
{
MuleApplication.Instance.Statistics.AddDownDataOverheadFileRequest(size);
SafeMemFile data_in = MpdObjectManager.CreateSafeMemFile(packet, offset, size);
byte[] reqfilehash = new byte[16];
data_in.ReadHash16(reqfilehash);
KnownFile reqfile = MuleApplication.Instance.SharedFiles.GetFileByID(reqfilehash);
bool bSenderMultipleIpUnknown = false;
UpDownClient sender =
MuleApplication.Instance.UploadQueue.GetWaitingClientByIP_UDP(ip, port,
true, ref bSenderMultipleIpUnknown);
if (reqfile == null)
{
Packet response =
MuleApplication.Instance.NetworkObjectManager.CreatePacket(OperationCodeEnum.OP_FILENOTFOUND,
0, MuleConstants.PROTOCOL_EMULEPROT);
MuleApplication.Instance.Statistics.AddUpDataOverheadFileRequest(response.Size);
if (sender != null)
{
SendPacket(response, ip, port, sender.ShouldReceiveCryptUDPPackets,
sender.UserHash, false, 0);
}
else
{
SendPacket(response, ip, port, false, null, false, 0);
}
break;
}
if (sender != null)
{
//Make sure we are still thinking about the same file
if (MpdUtilities.Md4Cmp(reqfilehash, sender.UploadFileID) == 0)
{
sender.AddAskedCount();
sender.SetLastUpRequest();
//I messed up when I first added extended info to UDP
//I should have originally used the entire ProcessExtenedInfo the first time.
//So now I am forced to check UDPVersion to see if we are sending all the extended info.
//For now on, we should not have to change anything here if we change
//anything to the extended info data as this will be taken care of in ProcessExtendedInfo()
//Update extended info.
if (sender.UDPVersion > 3)
{
sender.ProcessExtendedInfo(data_in, reqfile);
}
//Update our complete source counts.
else if (sender.UDPVersion > 2)
{
ushort nCompleteCountLast = sender.UpCompleteSourcesCount;
ushort nCompleteCountNew = data_in.ReadUInt16();
sender.UpCompleteSourcesCount = nCompleteCountNew;
if (nCompleteCountLast != nCompleteCountNew)
{
reqfile.UpdatePartsInfo();
}
}
SafeMemFile data_out = MpdObjectManager.CreateSafeMemFile(128);
if (sender.UDPVersion > 3)
{
if (reqfile.IsPartFile)
{
((PartFile)reqfile).WritePartStatus(data_out);
}
else
{
data_out.WriteUInt16(0);
}
}
data_out.WriteUInt16((ushort)(MuleApplication.Instance.UploadQueue.GetWaitingPosition(sender)));
Packet response =
MuleApplication.Instance.NetworkObjectManager.CreatePacket(data_out,
MuleConstants.PROTOCOL_EMULEPROT);
response.OperationCode = OperationCodeEnum.OP_REASKACK;
MuleApplication.Instance.Statistics.AddUpDataOverheadFileRequest(response.Size);
SendPacket(response, ip, port, sender.ShouldReceiveCryptUDPPackets,
sender.UserHash, false, 0);
}
}
else
{
// Don't answer him. We probably have him on our queue already, but can't locate him. Force him to establish a TCP connection
if (!bSenderMultipleIpUnknown)
{
if (((uint)MuleApplication.Instance.UploadQueue.WaitingUserCount + 50) >
MuleApplication.Instance.Preference.QueueSize)
{
Packet response =
MuleApplication.Instance.NetworkObjectManager.CreatePacket(OperationCodeEnum.OP_QUEUEFULL,
0, MuleConstants.PROTOCOL_EMULEPROT);
MuleApplication.Instance.Statistics.AddUpDataOverheadFileRequest(response.Size);
SendPacket(response, ip, port, false, null, false, 0); // we cannot answer this one encrypted since we dont know this client
}
}
}
break;
}
case OperationCodeEnum.OP_QUEUEFULL:
{
MuleApplication.Instance.Statistics.AddDownDataOverheadFileRequest(size);
UpDownClient sender = MuleApplication.Instance.DownloadQueue.GetDownloadClientByIP_UDP(ip, port, true);
if (sender != null && sender.UDPPacketPending)
{
sender.IsRemoteQueueFull = true;
sender.UDPReaskACK(0);
}
break;
}
case OperationCodeEnum.OP_REASKACK:
{
MuleApplication.Instance.Statistics.AddDownDataOverheadFileRequest(size);
UpDownClient sender =
MuleApplication.Instance.DownloadQueue.GetDownloadClientByIP_UDP(ip, port, true);
if (sender != null && sender.UDPPacketPending)
{
SafeMemFile data_in = MpdObjectManager.CreateSafeMemFile(packet, size);
if (sender.UDPVersion > 3)
{
sender.ProcessFileStatus(true, data_in, sender.RequestFile);
}
ushort nRank = data_in.ReadUInt16();
sender.IsRemoteQueueFull = false;
sender.UDPReaskACK(nRank);
sender.AddAskedCountDown();
}
break;
}
case OperationCodeEnum.OP_FILENOTFOUND:
{
MuleApplication.Instance.Statistics.AddDownDataOverheadFileRequest(size);
UpDownClient sender =
MuleApplication.Instance.DownloadQueue.GetDownloadClientByIP_UDP(ip, port, true);
if (sender != null && sender.UDPPacketPending)
{
sender.UDPReaskFNF(); // may delete 'sender'!
sender = null;
}
break;
}
case OperationCodeEnum.OP_PORTTEST:
{
MuleApplication.Instance.Statistics.AddDownDataOverheadOther(size);
if (size == 1)
{
if (packet[0] == 0x12)
{
bool ret = MuleApplication.Instance.ListenSocket.SendPortTestReply('1', true);
}
}
break;
}
case OperationCodeEnum.OP_DIRECTCALLBACKREQ:
{
if (!MuleApplication.Instance.ClientList.AllowCalbackRequest(ip))
{
break;
}
// do we accept callbackrequests at all?
if (MuleApplication.Instance.KadEngine.IsRunning &&
MuleApplication.Instance.KadEngine.IsFirewalled)
{
MuleApplication.Instance.ClientList.AddTrackCallbackRequests(ip);
SafeMemFile data = MpdObjectManager.CreateSafeMemFile(packet, size);
ushort nRemoteTCPPort = data.ReadUInt16();
byte[] uchUserHash = new byte[16];
data.ReadHash16(uchUserHash);
byte byConnectOptions = data.ReadUInt8();
UpDownClient pRequester =
MuleApplication.Instance.ClientList.FindClientByUserHash(uchUserHash, ip,
nRemoteTCPPort);
if (pRequester == null)
{
pRequester =
MuleApplication.Instance.CoreObjectManager.CreateUpDownClient(null,
nRemoteTCPPort, ip, 0, 0, true);
pRequester.UserHash = uchUserHash;
MuleApplication.Instance.ClientList.AddClient(pRequester);
}
pRequester.SetConnectOptions(byConnectOptions, true, false);
pRequester.DoesDirectUDPCallbackSupport = false;
pRequester.IP = ip;
pRequester.UserPort = nRemoteTCPPort;
pRequester.TryToConnect();
}
break;
}
default:
MuleApplication.Instance.Statistics.AddDownDataOverheadOther(size);
return(false);
}
return(true);
}