Mod protocol
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Revision as of 09:48, 10 July 2007 by 85.127.111.226 (Talk)
Contents |
Under construction
THIS IS NOT FINAL.. feel free to edit.
Introduction
Modprot is needed for more clean protocol extensions by eMule modders....
Documentation
All mod communication is to be done over the OP_MODPROT/OP_MODPACKEDPROT, When a hello(answer) with a set mod bit is received ConnectionEstablished is to be delayed, and instead the mod info packet with the opcode OP_MODINFO is ti be sent, ConnectionEstablished is to be triggered when the mod info packet is recived.
A B Hello ---> MB Set (see ModBit is set) MB Set <--- Hello Answer ConEst <--- MInfo (Mod Info) MInfo ---> ConEst (call ConnectionEstablished)
The mod info packet have to contain eEmuleTags that announces supported features:
<uint 32> tag count <emule tag 1> <emule tag 2> ... <emule tag n>
Only mod features are allowed to use that was announces by booth sided, after the capability exchange all reminding opcodes > 0x02 are allowed to be used by clients in any way they want. All furder communication is not part of this specification.
Protocol
Hello
Set the modbit ot in in CT_EMULE_MISCOPTIONS2
in baseclient.cpp, void CUpDownClient::SendHelloTypePacket(CSafeMemFile* data)
// eMule Misc. Options #2 const UINT uKadVersion = KADEMLIA_VERSION; const UINT uSupportLargeFiles = 1; const UINT uExtMultiPacket = 1; const UINT uReserved = 1; // mod bit const UINT uSupportsCryptLayer = thePrefs.IsClientCryptLayerSupported() ? 1 : 0; const UINT uRequestsCryptLayer = thePrefs.IsClientCryptLayerRequested() ? 1 : 0; const UINT uRequiresCryptLayer = thePrefs.IsClientCryptLayerRequired() ? 1 : 0; const UINT uSupportsSourceEx2 = 1; CTag tagMisOptions2(CT_EMULE_MISCOPTIONS2, // (RESERVED ) (uSupportsSourceEx2 << 10) | (uRequiresCryptLayer << 9) | (uRequestsCryptLayer << 8) | (uSupportsCryptLayer << 7) | (uReserved << 6) | (uExtMultiPacket << 5) | (uSupportLargeFiles << 4) | (uKadVersion << 0) ); tagMisOptions2.WriteTagToFile(data);
Process hello.
baseclient.cpp bool CUpDownClient::ProcessHelloTypePacket(CSafeMemFile* data)
case CT_EMULE_MISCOPTIONS2:
// 21 Reserved
// 1 Supports SourceExachnge2 Packets, ignores SX1 Packet Version
// 1 Requires CryptLayer
// 1 Requests CryptLayer
// 1 Supports CryptLayer
// 1 Reserved (ModBit)
// 1 Ext Multipacket (Hash+Size instead of Hash)
// 1 Large Files (includes support for 64bit tags)
// 4 Kad Version
if (temptag.IsInt()) {
m_fSupportsSourceEx2 = (temptag.GetInt() >> 10) & 0x01;
m_fRequiresCryptLayer = (temptag.GetInt() >> 9) & 0x01;
m_fRequestsCryptLayer = (temptag.GetInt() >> 8) & 0x01;
m_fSupportsCryptLayer = (temptag.GetInt() >> 7) & 0x01;
m_NeoModProtVersion = (temptag.GetInt() >> 6) & 0x01; // modbit NEO: NMP - [NeoModProt] <-- Xanatos --
m_fExtMultiPacket = (temptag.GetInt() >> 5) & 0x01;
m_fSupportsLargeFiles = (temptag.GetInt() >> 4) & 0x01;
m_byKadVersion = (uint8)((temptag.GetInt() >> 0) & 0x0f);
dwEmuleTags |= 8;
if (bDbgInfo)
m_strHelloInfo.AppendFormat(_T("\n KadVersion=%u, LargeFiles=%u ExtMultiPacket=%u CryptLayerSupport=%u CryptLayerRequest=%u CryptLayerRequires=%u m_fSupportsSourceEx2=%u"), m_byKadVersion, m_fSupportsLargeFiles, m_fExtMultiPacket, m_fSupportsCryptLayer, m_fRequestsCryptLayer, m_fRequiresCryptLayer, m_fSupportsSourceEx2);
m_fRequestsCryptLayer &= m_fSupportsCryptLayer;
m_fRequiresCryptLayer &= m_fRequestsCryptLayer;
==Send hello answer and modprot info ==
Listensocket.cpp bool CClientReqSocket::ProcessPacket(const BYTE* packet, uint32 size, UINT opcode)
if (client->GetHashType() == SO_EMULE && !bIsMuleHello)
client->SendMuleInfoPacket(false);
client->SendHelloAnswer();
if (client)
{
// NEO: NMP - [NeoModProt] -- Xanatos -->
if(client->GetNeoModProtVersion())
client->SendModInfoPacket();
Example of sendmoinfopacket:
void CUpDownClient::SendModInfoPacket(){
if (socket == NULL){
ASSERT(0);
return;
}
CSafeMemFile data(128);
uint32 tagcount=2+1;
#ifdef NATTUNNELING // NEO: NATT - [NatTraversal]
if(theApp.IsFirewalled() && Kademlia::CKademlia::IsConnected())
tagcount += 1;
#endif //NATTUNNELING // NEO: NATT END
data.WriteUInt32(tagcount); // nr. of tags
/************************************************************************************
* Note: The meaning of the bit fields in the current sample *
* have to be reworked for the final release version numbers are almost useless, *
* support (or newver version) should be anounced only by single bit flags *
************************************************************************************/
#ifdef NATTUNNELING // NEO: NATT - [NatTraversal]
const UINT uNatT = NeoPrefs.IsNatTraversalEnabled();
#endif //NATTUNNELING // NEO: NATT END
uint32 uNeoFeatures =
// ((0 & 0xff) << 24) | // Unused
// ((0 & 0x0f) << 20) | // Reserved
#ifdef NATTUNNELING // NEO: NATT - [NatTraversal]
// ((0 & 0x03) << 18) | // Reserved for nat-t
((1 & 0x01) << 17) | // NEO: RTP - [ReuseTCPPort]
((uNatT & 0x01) << 16) | // Support Nat Traversal
// ((0 & 0x01) << 15) | // NEO: XSB - [XSBuddy]
#endif //NATTUNNELING // NEO: NATT END
((1 & 0x07) << 12) | // NEO: NXS - [NeoXS]
// ((0 & 0x03) << 10) | // Reserved
((1 & 0x01) << 9 ) | // LowID UDP Ping Support (notifyes a fix form xman1 that allow the remote low ID to use udp reasks) // NEO: MOD - [NewUploadState]
((1 & 0x01) << 8 ) | // Unsolicited Part Status (allows our client ro recieve filestatus at any time) // NEO: USPS - [UnSolicitedPartStatus]
// ((0 & 0x0f) << 4 ) | // Reserved
((0 & 0x0f) << 0 );
CTag tagNeoModProt(CT_NEO_FEATURES, uNeoFeatures);
tagNeoModProt.WriteTagToFile(&data);
uint32 nSCT = NeoPrefs.UseSubChunkTransfer() ? 1 : 0; // version 4 bit
uint32 ICSv2 = NeoPrefs.UseIncompletePartStatus() ? 2 : 0; // version 3 bit
// X-ToDo:
//uint32 RPS = NeoPrefs.UseRealPartStatus() ? 1 : 0; // version 3 bit
//uint32 HPS = NeoPrefs.UseRealPartStatus() ? 1 : 0; // flag 1 bit
//uint32 BPS = NeoPrefs.UseRealPartStatus() ? 1 : 0; // flag 1 bit
uint32 uFileStatus =
// ((0 & 0xff) << 24) | // unused
// ((0 & 0xff) << 16) | // reserved
// ((BPS & 0x01) << 15) | // RPS Flag Blocked Parts
// ((HPS & 0x01) << 14) | // RPS Flag Hiden Parts
// ((RPS & 0x07) << 11) | // RPS VErsion
((ICSv2 & 0x07) << 8 ) | // ICSv2 Version
// ((0 & 0x0f) << 4 ) | // reserved
((nSCT & 0x0f) << 0 ); // SCT version
CTag tagPartStatus(CT_EXT_FILESTATUS,uFileStatus);
tagPartStatus.WriteNewEd2kTag(&data);
#ifdef NATTUNNELING // NEO: NATT - [NatTraversal]
if(theApp.IsFirewalled() && Kademlia::CKademlia::IsConnected())
{
// Note: to connect a cleint over his buddy or to request a calback we need not only his buddy IP/Port but also his Buddy ID
// So to get this realy to work we need to transmitt the buddy ID to
Kademlia::CUInt128 uBuddyID(true);
uBuddyID.Xor(Kademlia::CKademlia::GetPrefs()->GetKadID());
byte cID[16];
uBuddyID.ToByteArray(cID);
CTag tagBuddyID(CT_EMULE_BUDDYID, cID);
tagBuddyID.WriteNewEd2kTag(&data);
}
#endif //NATTUNNELING // NEO: NATT END
// Named tag test begin
LPCTSTR FunnyStr[3];
FunnyStr[0] = _T("Vote for the Pirate Party of your country");
FunnyStr[1] = _T("Have a nice day ;)");
FunnyStr[2] = _T("Confucius says: If you dont upload 10 GB/day good will punish you");
CTag tagMyMail("Mod:Hello",FunnyStr[rand()%ARRSIZE(FunnyStr)]);
tagMyMail.WriteNewEd2kTag(&data);
// Named tag test end
Packet* packet = new Packet(&data,OP_MODPROT);
packet->opcode = OP_MODINFOPACKET;
if (thePrefs.GetDebugClientTCPLevel() > 0)
DebugSend("OP__ModInfoPacket", this);
theStats.AddUpDataOverheadOther(packet->size);
socket->SendPacket(packet,true,true);
}
delay ConnectionEstablished & send mod info packet
listensocket.cpp
bool CClientReqSocket::ProcessPacket(const BYTE* packet, uint32 size, UINT opcode)
{
try
{
try
{
if (!client && opcode != OP_HELLO)
{
theStats.AddDownDataOverheadOther(size);
throw GetResString(IDS_ERR_NOHELLO);
}
else if (client && opcode != OP_HELLO && opcode != OP_HELLOANSWER)
client->CheckHandshakeFinished();
switch(opcode)
{
case OP_HELLOANSWER:
{
theStats.AddDownDataOverheadOther(size);
client->ProcessHelloAnswer(packet,size);
if (thePrefs.GetDebugClientTCPLevel() > 0){
DebugRecv("OP_HelloAnswer", client);
Debug(_T(" %s\n"), client->DbgGetHelloInfo());
}
// NEO: NMP - [NeoModProt] -- Xanatos -->
if(client->GetNeoModProtVersion() == 0)
// we will start the SUI when we recieve the mod info packet
// NEO: NMP END <-- Xanatos --
// start secure identification, if
// - we have received OP_EMULEINFO and OP_HELLOANSWER (old eMule)
// - we have received eMule-OP_HELLOANSWER (new eMule)
if (client->GetInfoPacketsReceived() == IP_BOTH)
client->InfoPacketsReceived();
if (client)
{
// NEO: NMP - [NeoModProt] -- Xanatos -->
if (client->GetNeoModProtVersion())
client->SendModInfoPacket();
else // we will call ConnectionEstablished when we recieve the Mod Info
// NEO: NMP END <-- Xanatos --
{
client->ConnectionEstablished();
theApp.emuledlg->transferwnd->clientlistctrl.RefreshClient(client);
}
}
break;
}
case OP_HELLO:
{
theStats.AddDownDataOverheadOther(size);
[...........................]
client->SendHelloAnswer();
if (client)
{
// NEO: NMP - [NeoModProt] -- Xanatos -->
if(client->GetNeoModProtVersion())
client->SendModInfoPacket();
else // we will call ConnectionEstablished when we recieve the Mod Info
// NEO: NMP END <-- Xanatos --
client->ConnectionEstablished();
}
ASSERT( client );
if(client)
{
// NEO: NMP - [NeoModProt] -- Xanatos -->
// we will start the SUI when we recieve the mod info packet
if(client->GetNeoModProtVersion() == 0)
// NEO: NMP END <-- Xanatos --
// start secure identification, if
// - we have received eMule-OP_HELLO (new eMule)
if (client->GetInfoPacketsReceived() == IP_BOTH)
client->InfoPacketsReceived();
if( client->GetKadPort() )
Kademlia::CKademlia::Bootstrap(ntohl(client->GetIP()), client->GetKadPort(), (client->GetKadVersion() > 1));
}
break;
}
process modinfo packet
listensocket.cpp
bool CClientReqSocket::ProcessModPacket(const BYTE* packet, uint32 size, UINT opcode, UINT uRawSize)
{
try
{
try
{
if (!client)
{
theStats.AddDownDataOverheadOther(uRawSize);
throw GetResString(IDS_ERR_UNKNOWNCLIENTACTION);
}
if (thePrefs.m_iDbgHeap >= 2)
ASSERT_VALID(client);
switch(opcode)
{
case OP_MODINFOPACKET:
{
if (thePrefs.GetDebugClientTCPLevel() > 0)
DebugRecv("OP__ModInfoPacket", client);
theStats.AddDownDataOverheadOther(uRawSize);
if(client->GetNeoModProtVersion() == 0)
throw CString(_T("Recieved Neo Mod Info Packet from a cleint whitch doe snot support this feature!"));
client->ProcessModInfoPacket(packet,size);
// Now after we have all informations about the cleint the connection is established
client->ConnectionEstablished();
// start secure identification, if
// - we have received OP_MODINFOPACKET, (Neo Compatible new eMule mods)
if (client->GetInfoPacketsReceived() == IP_BOTH)
client->InfoPacketsReceived();
break;
}
// NEO: NMPm - [NeoModProtMultiPacket]
case OP_MODMULTIPACKET:
{
...
baseclient.cpp
void CUpDownClient::ProcessModInfoPacket(const uchar* pachPacket, uint32 nSize)
{
bool bDbgInfo = thePrefs.GetUseDebugDevice();
CString m_strModInfo;
CSafeMemFile data(pachPacket, nSize);
uint32 tagcount = data.ReadUInt32();
if (bDbgInfo)
m_strModInfo.AppendFormat(_T(" Tags=%u"), (UINT)tagcount);
for (uint32 i = 0; i < tagcount; i++)
{
CTag temptag(&data, false);
switch (temptag.GetNameID())
{
case CT_NEO_FEATURES:
if (temptag.IsInt()){
// = (uint8)(temptag.GetInt() >> 24) & 0xff;
// = (uint8)(temptag.GetInt() >> 20) & 0x0f;
#ifdef NATTUNNELING // NEO: NATT - [NatTraversal]
// = (uint8)(temptag.GetInt() >> 18) & 0x03;
m_PublicPortReport = (uint8)(temptag.GetInt() >> 17) & 0x01; // NEO: RTP - [ReuseTCPPort]
m_SupportsNatTraversal = (uint8)(temptag.GetInt() >> 16) & 0x01;
// = (uint8)(temptag.GetInt() >> 15) & 0x01; // NEO: XSB - [XSBuddy]
#endif //NATTUNNELING // NEO: NATT END
m_NeoXSVersion = (uint8)(temptag.GetInt() >> 12) & 0x07; // NEO: NXS - [NeoXS]
// = (uint8)(temptag.GetInt() >> 10) & 0x03;
m_LowIDUDPPingSupport = (uint8)(temptag.GetInt() >> 9 ) & 0x01;
m_UnsolicitedPartStatus = (uint8)(temptag.GetInt() >> 8 ) & 0x01;
// = (uint8)(temptag.GetInt() >> 4 ) & 0x0f;
// = (uint8)(temptag.GetInt() >> 0 ) & 0x0f;
}else if (bDbgInfo)
m_strHelloInfo.AppendFormat(_T("\n ***UnkType=%s"), temptag.GetFullInfo());
break;
case CT_EXT_FILESTATUS:
if (temptag.IsInt()){
// X-ToDo
// = (uint8)(temptag.GetInt() >> 24) & 0xff;
// = (uint8)(temptag.GetInt() >> 16) & 0xff;
//uint8 BlockedPartStatus = (uint8)(temptag.GetInt() >> 15) & 0x01;
//uint8 HidenPartStatus = (uint8)(temptag.GetInt() >> 14) & 0x01;
//uint8 RealPartStatusVer = (uint8)(temptag.GetInt() >> 11) & 0x07;
m_IncompletePartVer = (uint8)(temptag.GetInt() >> 8 ) & 0x07;
// = (uint8)(temptag.GetInt() >> 4 ) & 0x0f;
m_SubChunksVer = (uint8)(temptag.GetInt() >> 0 ) & 0x0f;
//ASSERT(BlockedPartStatus || HidenPartStatus || !RealPartStatusVer);
// Note: RPC version without one or booth RPS flags is invalid,
// the cleint must always say wha is he doint gith the parts 'blocking and hiding' or 'only hiding',
// or he can booth depanding on the situation
// Booth RPS versions have always teh same version as the writing functions are identical
// just other opcodes are used and other part states notifyed
//if(BlockedPartStatus)
// m_BlockedPartStatusVer = RealPartStatusVer;
//if(HidenPartStatus)
// m_HidenPartStatusVer = RealPartStatusVer;
}else if (bDbgInfo)
m_strModInfo.AppendFormat(_T("\n ***UnkType=%s"), temptag.GetFullInfo());
break;
#ifdef NATTUNNELING // NEO: NATT - [NatTraversal]
case CT_EMULE_BUDDYID:
if(temptag.IsHash())
{
SetBuddyID(temptag.GetHash());
}
else{
if (bDbgInfo)
m_strModInfo.AppendFormat(_T("\n ***UnkType=%s"), temptag.GetFullInfo());
}
break;
#endif //NATTUNNELING // NEO: NATT END
default:
// Named tag test begin
if(strcmp(temptag.GetName(),"Mod:Hello") == 0)
{
if(temptag.IsStr())
Log(LOG_SUCCESS,_T("*** Greathings from %s: %s"),GetUserName(),temptag.GetStr());
}
else
// Named tag test end
if (bDbgInfo)
m_strModInfo.AppendFormat(_T("\n ***UnkTag=%s"), temptag.GetFullInfo());
}
}
proces mod data example
listensocket.cpp bool CClientReqSocket::PacketReceivedCppEH(Packet* packet)
// NEO: NMP - [NeoModProt] -- Xanatos -->
case OP_MODPACKEDPROT:
if (!packet->UnPackPacket()){
if (thePrefs.GetVerbose())
AddDebugLogLine(false, _T("Failed to decompress client Mod TCP packet; %s; %s"), DbgGetClientTCPPacket(packet->prot, packet->opcode, packet->size), DbgGetClientInfo());
bResult = false;
break;
}
case OP_MODPROT:
bResult = ProcessModPacket((const BYTE*)packet->pBuffer, packet->size, packet->opcode, uRawSize);
break;
// NEO: NMP - [NeoModProt] -- Xanatos -->
bool CClientReqSocket::ProcessModPacket(const BYTE* packet, uint32 size, UINT opcode, UINT uRawSize)
{
try
{
try
{
if (!client)
{
theStats.AddDownDataOverheadOther(uRawSize);
throw GetResString(IDS_ERR_UNKNOWNCLIENTACTION);
}
if (thePrefs.m_iDbgHeap >= 2)
ASSERT_VALID(client);
switch(opcode)
{
case OP_MODINFOPACKET:
{
if (thePrefs.GetDebugClientTCPLevel() > 0)
DebugRecv("OP__ModInfoPacket", client);
theStats.AddDownDataOverheadOther(uRawSize);
if(client->GetNeoModProtVersion() == 0)
throw CString(_T("Recieved Neo Mod Info Packet from a cleint whitch doe snot support this feature!"));
client->ProcessModInfoPacket(packet,size);
// Now after we have all informations about the cleint the connection is established
client->ConnectionEstablished();
// start secure identification, if
// - we have received OP_MODINFOPACKET, (Neo Compatible new eMule mods)
if (client->GetInfoPacketsReceived() == IP_BOTH)
client->InfoPacketsReceived();
break;
}
default:
theStats.AddDownDataOverheadOther(uRawSize);
PacketToDebugLogLine(_T("ModProt"), packet, size, opcode);
}
}
catch(CFileException* error)
{
error->Delete();
throw GetResString(IDS_ERR_INVALIDPACKAGE);
}
catch(CMemoryException* error)
{
error->Delete();
throw CString(_T("Memory exception"));
}
}
catch(CString error)
{
if (thePrefs.GetVerbose() && !error.IsEmpty())
DebugLogWarning(_T("Error: %s - while processing Mod packet: opcode=%s size=%u; %s"), error, DbgGetMuleClientTCPOpcode(opcode), size, DbgGetClientInfo());
// Note: don't disconnect cleints on mod prot errors, the extensions are just addons and if thay fail the client will work anyway
//if (client)
// client->SetDownloadState(DS_ERROR, _T("ProcessModPacket error. ") + error);
//Disconnect(_T("ProcessModPacket error. ") + error);
//return false;
}
return true;
}
// NEO: NMP END <-- Xanatos --
backward compatibility
Modstring is still send and replied in hello packet to maintain backward compatibility However a opcode for modstring will be defined for those who alos want to move it to the mod protocol
