]> git.netwichtig.de Git - user/henk/code/inspircd.git/blobdiff - src/modules/m_spanningtree/treesocket2.cpp
Fix potential for duplicate SID if the SID is auto generated.
[user/henk/code/inspircd.git] / src / modules / m_spanningtree / treesocket2.cpp
index 0971a87c517c8373ec14440a3c6e077eea99c28c..34cf318e30d9ec7488d445ca500d89db9b73f53a 100644 (file)
@@ -11,6 +11,7 @@
  * ---------------------------------------------------
  */
 
+#include "inspircd.h"
 #include "configreader.h"
 #include "users.h"
 #include "channels.h"
@@ -18,7 +19,6 @@
 #include "commands/cmd_whois.h"
 #include "commands/cmd_stats.h"
 #include "socket.h"
-#include "inspircd.h"
 #include "wildcard.h"
 #include "xline.h"
 #include "transport.h"
 
 /* $ModDep: m_spanningtree/timesynctimer.h m_spanningtree/resolvers.h m_spanningtree/main.h m_spanningtree/utils.h m_spanningtree/treeserver.h m_spanningtree/link.h m_spanningtree/treesocket.h */
 
+static std::map<std::string, std::string> warned;       /* Server names that have had protocol violation warnings displayed for them */
+
 int TreeSocket::WriteLine(std::string line)
 {
-       Instance->Log(DEBUG, "-> %s", line.c_str());
+       Instance->Log(DEBUG, "S[%d] -> %s", this->GetFd(), line.c_str());
        line.append("\r\n");
        return this->Write(line);
 }
 
+
 /* Handle ERROR command */
 bool TreeSocket::Error(std::deque<std::string> &params)
 {
        if (params.size() < 1)
                return false;
-       this->Instance->SNO->WriteToSnoMask('l',"ERROR from %s: %s",(InboundServerName != "" ? InboundServerName.c_str() : myhost.c_str()),params[0].c_str());
+       this->Instance->SNO->WriteToSnoMask('l',"ERROR from %s: %s",(!InboundServerName.empty() ? InboundServerName.c_str() : myhost.c_str()),params[0].c_str());
        /* we will return false to cause the socket to close. */
        return false;
 }
@@ -139,7 +142,7 @@ bool TreeSocket::Motd(const std::string &prefix, std::deque<std::string> &params
                                        Utils->DoOneToOne(this->Instance->Config->ServerName, "PUSH",par, source->server);
                                }
 
-                               par[1] = std::string("::")+Instance->Config->ServerName+" 376 "+source->nick+" End of message of the day.";
+                               par[1] = std::string("::")+Instance->Config->ServerName+" 376 "+source->nick+" :End of message of the day.";
                                Utils->DoOneToOne(this->Instance->Config->ServerName, "PUSH",par, source->server);
                        }
                }
@@ -242,7 +245,28 @@ bool TreeSocket::OperType(const std::string &prefix, std::deque<std::string> &pa
                this->Instance->all_opers.push_back(u);
                strlcpy(u->oper,opertype.c_str(),NICKMAX-1);
                Utils->DoOneToAllButSender(u->nick,"OPERTYPE",params,u->server);
-               this->Instance->SNO->WriteToSnoMask('o',"From %s: User %s (%s@%s) is now an IRC operator of type %s",u->server, u->nick,u->ident,u->host,irc::Spacify(opertype.c_str()));
+
+               TreeServer* remoteserver=Utils->FindServer(u->server);
+               bool dosend = true;
+
+               if (this->Utils->quiet_bursts)
+               {
+                       /*
+                        * If quiet bursts are enabled, and server is bursting or silent uline (i.e. services),
+                        * then do nothing. -- w00t
+                        */
+                       if (
+                               this->bursting ||
+                               Utils->FindRemoteBurstServer(remoteserver) ||
+                               this->Instance->SilentULine(this->Instance->FindServerNamePtr(u->server))
+                          )
+                       {
+                               dosend = false;
+                       }
+               }
+
+               if (dosend)
+                       this->Instance->SNO->WriteToSnoMask('o',"From %s: User %s (%s@%s) is now an IRC operator of type %s",u->server, u->nick,u->ident,u->host,irc::Spacify(opertype.c_str()));
        }
        return true;
 }
@@ -260,18 +284,26 @@ bool TreeSocket::ForceNick(const std::string &prefix, std::deque<std::string> &p
        if (u)
        {
                Utils->DoOneToAllButSender(prefix,"SVSNICK",params,prefix);
+
                if (IS_LOCAL(u))
                {
                        std::deque<std::string> par;
                        par.push_back(params[1]);
+
                        if (!u->ForceNickChange(params[1].c_str()))
                        {
-                               userrec::QuitUser(this->Instance, u, "Nickname collision");
-                               return true;
+                               /* buh. UID them */
+                               if (!u->ForceNickChange(u->uuid))
+                               {
+                                       userrec::QuitUser(this->Instance, u, "Nickname collision");
+                                       return true;
+                               }
                        }
+
                        u->age = atoi(params[2].c_str());
                }
        }
+
        return true;
 }
 
@@ -284,62 +316,19 @@ bool TreeSocket::OperQuit(const std::string &prefix, std::deque<std::string> &pa
 
        if (u)
        {
-               Utils->DoOneToAllButSender(prefix,"OPERQUIT",params,prefix);
                u->SetOperQuit(params[0]);
+               params[0] = ":" + params[0];
+               Utils->DoOneToAllButSender(prefix,"OPERQUIT",params,prefix);
        }
        return true;
 }
 
-/*
- * Remote SQUIT (RSQUIT). Routing works similar to SVSNICK: Route it to the server that the target is connected to locally,
- * then let that server do the dirty work (squit it!). Example:
- * A -> B -> C -> D: oper on A squits D, A routes to B, B routes to C, C notices D connected locally, kills it. -- w00t
- */
-bool TreeSocket::RemoteSquit(const std::string &prefix, std::deque<std::string> &params)
+bool TreeSocket::ServiceJoin(const std::string &prefix, std::deque<std::string> &params)
 {
-       /* ok.. :w00t RSQUIT jupe.barafranca.com :reason here */
        if (params.size() < 2)
                return true;
 
-       TreeServer* s = Utils->FindServerMask(params[0]);
-
-       if (s)
-       {
-               if (s == Utils->TreeRoot)
-               {
-                       this->Instance->SNO->WriteToSnoMask('l',"What the fuck, I recieved a remote SQUIT for myself? :< (from %s", prefix.c_str());
-                       return true;
-               }
-
-               TreeSocket* sock = s->GetSocket();
-
-               if (sock)
-               {
-                       /* it's locally connected, KILL IT! */
-                       Instance->SNO->WriteToSnoMask('l',"RSQUIT: Server \002%s\002 removed from network by %s: %s", params[0].c_str(), prefix.c_str(), params[1].c_str());
-                       sock->Squit(s,"Server quit by " + prefix + ": " + params[1]);
-                       Instance->SE->DelFd(sock);
-                       sock->Close();
-                       delete sock;
-               }
-               else
-               {
-                       /* route the rsquit */
-                       params[1] = ":" + params[1];
-                       Utils->DoOneToOne(prefix, "RSQUIT", params, params[0]);
-               }
-       }
-       else
-       {
-               /* mother fucker! it doesn't exist */
-       }
-
-       return true;
-}
-
-bool TreeSocket::ServiceJoin(const std::string &prefix, std::deque<std::string> &params)
-{
-       if (params.size() < 2)
+       if (!this->Instance->IsChannel(params[1].c_str()))
                return true;
 
        userrec* u = this->Instance->FindNick(params[0]);
@@ -373,30 +362,25 @@ bool TreeSocket::RemoteRehash(const std::string &prefix, std::deque<std::string>
 }
 
 bool TreeSocket::RemoteKill(const std::string &prefix, std::deque<std::string> &params)
-{
+{       
        if (params.size() != 2)
                return true;
 
-       std::string nick = params[0];
-       userrec* u = this->Instance->FindNick(prefix);
-       userrec* who = this->Instance->FindNick(nick);
+       userrec* who = this->Instance->FindNick(params[0]);
 
        if (who)
        {
-               /* Prepend kill source, if we don't have one */
-               std::string sourceserv = prefix;
-               if (u)
-               {
-                       sourceserv = u->server;
-               }
+               /* Prepend kill source, if we don't have one */          
                if (*(params[1].c_str()) != '[')
                {
-                       params[1] = "[" + sourceserv + "] Killed (" + params[1] +")";
+                       params[1] = "[" + prefix + "] Killed (" + params[1] +")";
                }
                std::string reason = params[1];
                params[1] = ":" + params[1];
-               Utils->DoOneToAllButSender(prefix,"KILL",params,sourceserv);
-               who->Write(":%s KILL %s :%s (%s)", sourceserv.c_str(), who->nick, sourceserv.c_str(), reason.c_str());
+               Utils->DoOneToAllButSender(prefix,"KILL",params,prefix);
+               // NOTE: This is safe with kill hiding on, as RemoteKill is only reached if we have a server prefix.
+               // in short this is not executed for USERS.
+               who->Write(":%s KILL %s :%s (%s)", prefix.c_str(), who->nick, prefix.c_str(), reason.c_str());
                userrec::QuitUser(this->Instance,who,reason);
        }
        return true;
@@ -413,7 +397,10 @@ bool TreeSocket::LocalPong(const std::string &prefix, std::deque<std::string> &p
                if (ServerSource)
                {
                        ServerSource->SetPingFlag();
-                       ServerSource->rtt = Instance->Time() - ServerSource->LastPing;
+                       timeval t;
+                       gettimeofday(&t, NULL);
+                       long ts = (t.tv_sec * 1000) + (t.tv_usec / 1000);
+                       ServerSource->rtt = ts - ServerSource->LastPingMsec;
                }
        }
        else
@@ -447,11 +434,13 @@ bool TreeSocket::MetaData(const std::string &prefix, std::deque<std::string> &pa
 {
        if (params.size() < 2)
                return true;
-       else
+       else if (params.size() < 3)
                params.push_back("");
        TreeServer* ServerSource = Utils->FindServer(prefix);
        if (ServerSource)
        {
+               Utils->SetRemoteBursting(ServerSource, false);
+
                if (params[0] == "*")
                {
                        FOREACH_MOD_I(this->Instance,I_OnDecodeMetaData,OnDecodeMetaData(TYPE_OTHER,NULL,params[1],params[2]));
@@ -604,19 +593,20 @@ bool TreeSocket::Whois(const std::string &prefix, std::deque<std::string> &param
                                userrec* x = this->Instance->FindNick(params[0]);
                                char signon[MAXBUF];
                                char idle[MAXBUF];
-                               snprintf(signon,MAXBUF,"%lu",(unsigned long)x->signon);
-                               snprintf(idle,MAXBUF,"%lu",(unsigned long)abs((x->idle_lastmsg)-Instance->Time(true)));
+                               snprintf(signon, MAXBUF, "%lu", (unsigned long)x->signon);
+                               snprintf(idle, MAXBUF, "%lu", (unsigned long)abs((x->idle_lastmsg) - Instance->Time(true)));
                                std::deque<std::string> par;
                                par.push_back(prefix);
                                par.push_back(signon);
                                par.push_back(idle);
                                // ours, we're done, pass it BACK
-                               Utils->DoOneToOne(params[0],"IDLE",par,u->server);
+                               Utils->DoOneToOne(params[0], "IDLE", par, u->server);
                        }
                        else
                        {
                                // not ours pass it on
-                               Utils->DoOneToOne(prefix,"IDLE",params,x->server);
+                               if (x)
+                                       Utils->DoOneToOne(prefix, "IDLE", params, x->server);
                        }
                }
                else if (params.size() == 3)
@@ -630,12 +620,15 @@ bool TreeSocket::Whois(const std::string &prefix, std::deque<std::string> &param
                                unsigned long signon = atoi(params[1].c_str());
                                unsigned long idle = atoi(params[2].c_str());
                                if ((who_to_send_to) && (IS_LOCAL(who_to_send_to)))
-                                       do_whois(this->Instance,who_to_send_to,u,signon,idle,nick_whoised.c_str());
+                               {
+                                       do_whois(this->Instance, who_to_send_to, u, signon, idle, nick_whoised.c_str());
+                               }
                        }
                        else
                        {
                                // not ours, pass it on
-                               Utils->DoOneToOne(prefix,"IDLE",params,who_to_send_to->server);
+                               if (who_to_send_to)
+                                       Utils->DoOneToOne(prefix, "IDLE", params, who_to_send_to->server);
                        }
                }
        }
@@ -786,59 +779,98 @@ bool TreeSocket::RemoveStatus(const std::string &prefix, std::deque<std::string>
 
 bool TreeSocket::RemoteServer(const std::string &prefix, std::deque<std::string> &params)
 {
-       if (params.size() < 4)
+       if (params.size() < 5)
                return false;
        std::string servername = params[0];
        std::string password = params[1];
        // hopcount is not used for a remote server, we calculate this ourselves
-       std::string description = params[3];
+       std::string sid = params[3];
+       std::string description = params[4];
        TreeServer* ParentOfThis = Utils->FindServer(prefix);
        if (!ParentOfThis)
        {
-               this->WriteLine("ERROR :Protocol error - Introduced remote server from unknown server "+prefix);
+               this->SendError("Protocol error - Introduced remote server from unknown server "+prefix);
                return false;
        }
        TreeServer* CheckDupe = Utils->FindServer(servername);
        if (CheckDupe)
        {
-               this->WriteLine("ERROR :Server "+servername+" already exists!");
+               this->SendError("Server "+servername+" already exists!");
                this->Instance->SNO->WriteToSnoMask('l',"Server \2"+servername+"\2 being introduced from \2" + prefix + "\2 denied, already exists. Closing link with " + prefix);
                return false;
        }
+
        Link* lnk = Utils->FindLink(servername);
-       TreeServer* Node = new TreeServer(this->Utils,this->Instance,servername,description,ParentOfThis,NULL, lnk ? lnk->Hidden : false);
+
+       TreeServer *Node = new TreeServer(this->Utils, this->Instance, servername, description, sid, ParentOfThis,NULL, lnk ? lnk->Hidden : false);
+
+       if (Node->DuplicateID())
+       {
+               this->SendError("Server ID "+sid+" already exists on the network!");
+               this->Instance->SNO->WriteToSnoMask('l',"Server \2"+servername+"\2 being introduced from \2" + prefix + "\2 denied, server ID already exists on the network. Closing link with " + prefix);
+               return false;
+       }
+
        ParentOfThis->AddChild(Node);
-       params[3] = ":" + params[3];
+       params[4] = ":" + params[4];
+       Utils->SetRemoteBursting(Node, true);
        Utils->DoOneToAllButSender(prefix,"SERVER",params,prefix);
        this->Instance->SNO->WriteToSnoMask('l',"Server \002"+prefix+"\002 introduced server \002"+servername+"\002 ("+description+")");
        return true;
 }
 
+bool TreeSocket::ComparePass(const std::string &ours, const std::string &theirs)
+{
+       if ((!strncmp(ours.c_str(), "HMAC-SHA256:", 12)) || (!strncmp(theirs.c_str(), "HMAC-SHA256:", 12)))
+       {
+               /* One or both of us specified hmac sha256, but we don't have sha256 module loaded!
+                * We can't allow this password as valid.
+                */
+               if (!Instance->FindModule("m_sha256.so") || !Utils->ChallengeResponse)
+                               return false;
+               else
+                       /* Straight string compare of hashes */
+                       return ours == theirs;
+       }
+       else
+               /* Straight string compare of plaintext */
+               return ours == theirs;
+}
+
 bool TreeSocket::Outbound_Reply_Server(std::deque<std::string> &params)
 {
-       if (params.size() < 4)
+       if (params.size() < 5)
                return false;
 
        irc::string servername = params[0].c_str();
        std::string sname = params[0];
        std::string password = params[1];
+       std::string sid = params[3];
+       std::string description = params[4];
        int hops = atoi(params[2].c_str());
 
+       this->InboundServerName = sname;
+       this->InboundDescription = description;
+       this->InboundSID = sid;
+
+       if (!sentcapab)
+               this->SendCapabilities();
+
        if (hops)
        {
-               this->WriteLine("ERROR :Server too far away for authentication");
+               this->SendError("Server too far away for authentication");
                this->Instance->SNO->WriteToSnoMask('l',"Server connection from \2"+sname+"\2 denied, server is too far away for authentication");
                return false;
        }
-       std::string description = params[3];
+
        for (std::vector<Link>::iterator x = Utils->LinkBlocks.begin(); x < Utils->LinkBlocks.end(); x++)
        {
-               if ((x->Name == servername) && (x->RecvPass == password))
+               if ((x->Name == servername) && ((ComparePass(this->MakePass(x->RecvPass,this->GetOurChallenge()),password)) || (x->RecvPass == password && (this->GetTheirChallenge().empty()))))
                {
                        TreeServer* CheckDupe = Utils->FindServer(sname);
                        if (CheckDupe)
                        {
-                               this->WriteLine("ERROR :Server "+sname+" already exists on server "+CheckDupe->GetParent()->GetName()+"!");
+                               this->SendError("Server "+sname+" already exists on server "+CheckDupe->GetParent()->GetName()+"!");
                                this->Instance->SNO->WriteToSnoMask('l',"Server connection from \2"+sname+"\2 denied, already exists on server "+CheckDupe->GetParent()->GetName());
                                return false;
                        }
@@ -850,44 +882,90 @@ bool TreeSocket::Outbound_Reply_Server(std::deque<std::string> &params)
                        // we should add the details of this server now
                        // to the servers tree, as a child of the root
                        // node.
-                       TreeServer* Node = new TreeServer(this->Utils,this->Instance,sname,description,Utils->TreeRoot,this,x->Hidden);
+
+                       TreeServer *Node = new TreeServer(this->Utils, this->Instance, sname, description, sid, Utils->TreeRoot, this, x->Hidden);
+
+                       if (Node->DuplicateID())
+                       {
+                               this->SendError("Server ID "+sid+" already exists on the network!");
+                               this->Instance->SNO->WriteToSnoMask('l',"Server \2"+assign(servername)+"\2 being introduced denied, server ID already exists on the network. Closing link.");
+                               return false;
+                       }
+
                        Utils->TreeRoot->AddChild(Node);
-                       params[3] = ":" + params[3];
+                       params[4] = ":" + params[4];
                        Utils->DoOneToAllButSender(Utils->TreeRoot->GetName(),"SERVER",params,sname);
                        this->bursting = true;
                        this->DoBurst(Node);
                        return true;
                }
        }
-       this->WriteLine("ERROR :Invalid credentials");
+       this->SendError("Invalid credentials");
        this->Instance->SNO->WriteToSnoMask('l',"Server connection from \2"+sname+"\2 denied, invalid link credentials");
        return false;
 }
 
 bool TreeSocket::Inbound_Server(std::deque<std::string> &params)
 {
-       if (params.size() < 4)
+       if (params.size() < 5)
                return false;
        irc::string servername = params[0].c_str();
        std::string sname = params[0];
        std::string password = params[1];
+       std::string sid = params[3];
+       std::string description = params[4];
+       std::string OurSID;
        int hops = atoi(params[2].c_str());
 
+       this->InboundServerName = sname;
+       this->InboundDescription = description;
+       this->InboundSID = sid;
+
+       OurSID += (char)((Instance->Config->sid / 100) + 48);
+       OurSID += (char)((Instance->Config->sid / 10) % 10 + 48);
+       OurSID += (char)(Instance->Config->sid % 10 + 48);
+
+       if (!sentcapab)
+               this->SendCapabilities();
+
        if (hops)
        {
-               this->WriteLine("ERROR :Server too far away for authentication");
+               this->SendError("Server too far away for authentication");
                this->Instance->SNO->WriteToSnoMask('l',"Server connection from \2"+sname+"\2 denied, server is too far away for authentication");
                return false;
        }
-       std::string description = params[3];
+
        for (std::vector<Link>::iterator x = Utils->LinkBlocks.begin(); x < Utils->LinkBlocks.end(); x++)
        {
-               if ((x->Name == servername) && (x->RecvPass == password))
+               if ((x->Name == servername) && ((ComparePass(this->MakePass(x->RecvPass,this->GetOurChallenge()),password) || x->RecvPass == password && (this->GetTheirChallenge().empty()))))
                {
+                       /* First check for instances of the server that are waiting between the inbound and outbound SERVER command */
+                       TreeSocket* CheckDupeSocket = Utils->FindBurstingServer(sname);
+                       if (CheckDupeSocket)
+                       {
+                               /* If we find one, we abort the link to prevent a race condition */
+                               this->SendError("Negotiation collision");
+                               this->Instance->SNO->WriteToSnoMask('l',"Server connection from \2"+sname+"\2 denied, already exists in a negotiating state.");
+                               CheckDupeSocket->SendError("Negotiation collision");
+                               Instance->SE->DelFd(CheckDupeSocket);
+                               CheckDupeSocket->Close();
+                               return false;
+                       }
+                       /* Check for fully initialized instances of the server by id */
+                       Instance->Log(DEBUG,"Looking for dupe SID %s", sid.c_str());
+                       TreeServer* CheckDupeSID = Utils->FindServerID(sid);
+                       if (CheckDupeSID)
+                       {
+                               this->SendError("Server ID "+CheckDupeSID->GetID()+" already exists on server "+CheckDupeSID->GetName()+"!");
+                               this->Instance->SNO->WriteToSnoMask('l',"Server connection from \2"+sname+"\2 denied, server ID '"+CheckDupeSID->GetID()+
+                                               "' already exists on server "+CheckDupeSID->GetName());
+                               return false;
+                       }
+                       /* Now check for fully initialized instances of the server by name */
                        TreeServer* CheckDupe = Utils->FindServer(sname);
                        if (CheckDupe)
                        {
-                               this->WriteLine("ERROR :Server "+sname+" already exists on server "+CheckDupe->GetParent()->GetName()+"!");
+                               this->SendError("Server "+sname+" already exists on server "+CheckDupe->GetParent()->GetName()+"!");
                                this->Instance->SNO->WriteToSnoMask('l',"Server connection from \2"+sname+"\2 denied, already exists on server "+CheckDupe->GetParent()->GetName());
                                return false;
                        }
@@ -898,17 +976,17 @@ bool TreeSocket::Inbound_Server(std::deque<std::string> &params)
                                this->Instance->SNO->WriteToSnoMask('l',"Connection from \2"+sname+"\2["+(x->HiddenFromStats ? "<hidden>" : this->GetIP())+"] using transport \2"+name+"\2");
                        }
 
-                       this->InboundServerName = sname;
-                       this->InboundDescription = description;
+                       Utils->AddBurstingServer(sname,this);
+
                        // this is good. Send our details: Our server name and description and hopcount of 0,
                        // along with the sendpass from this block.
-                       this->WriteLine(std::string("SERVER ")+this->Instance->Config->ServerName+" "+this->MakePass(x->SendPass, this->GetTheirChallenge())+" 0 :"+this->Instance->Config->ServerDesc);
+                       this->WriteLine(std::string("SERVER ")+this->Instance->Config->ServerName+" "+this->MakePass(x->SendPass, this->GetTheirChallenge())+" 0 "+OurSID+" :"+this->Instance->Config->ServerDesc);
                        // move to the next state, we are now waiting for THEM.
                        this->LinkState = WAIT_AUTH_2;
                        return true;
                }
        }
-       this->WriteLine("ERROR :Invalid credentials");
+       this->SendError("Invalid credentials");
        this->Instance->SNO->WriteToSnoMask('l',"Server connection from \2"+sname+"\2 denied, invalid link credentials");
        return false;
 }
@@ -919,7 +997,10 @@ void TreeSocket::Split(const std::string &line, std::deque<std::string> &n)
        irc::tokenstream tokens(line);
        std::string param;
        while (tokens.GetToken(param))
-               n.push_back(param);
+       {
+               if (!param.empty())
+                       n.push_back(param);
+       }
        return;
 }
 
@@ -934,10 +1015,13 @@ bool TreeSocket::ProcessLine(std::string &line)
        if (line.empty())
                return true;
 
-       Instance->Log(DEBUG, "<- %s", line.c_str());
+       Instance->Log(DEBUG, "S[%d] <- %s", this->GetFd(), line.c_str());
 
        this->Split(line.c_str(),params);
-
+       
+       if (params.empty())
+               return true;
+       
        if ((params[0][0] == ':') && (params.size() > 1))
        {
                prefix = params[0].substr(1);
@@ -969,23 +1053,17 @@ bool TreeSocket::ProcessLine(std::string &line)
                        }
                        else if (command == "USER")
                        {
-                               this->WriteLine("ERROR :Client connections to this port are prohibited.");
+                               this->SendError("Client connections to this port are prohibited.");
                                return false;
                        }
                        else if (command == "CAPAB")
                        {
                                return this->Capab(params);
                        }
-                       else if ((command == "U") || (command == "S"))
-                       {
-                               this->WriteLine("ERROR :Cannot use the old-style mesh linking protocol with m_spanningtree.so!");
-                               return false;
-                       }
                        else
                        {
-                               std::string error("ERROR :Invalid command in negotiation phase: ");
-                               error.append(command.c_str());
-                               this->WriteLine(error);
+                               irc::string error = "Invalid command in negotiation phase: " + command;
+                               this->SendError(assign(error));
                                return false;
                        }
                break;
@@ -998,11 +1076,6 @@ bool TreeSocket::ProcessLine(std::string &line)
                                // silently ignore.
                                return true;
                        }
-                       else if ((command == "U") || (command == "S"))
-                       {
-                               this->WriteLine("ERROR :Cannot use the old-style mesh linking protocol with m_spanningtree.so!");
-                               return false;
-                       }
                        else if (command == "BURST")
                        {
                                if (params.size() && Utils->EnableTimeSync)
@@ -1010,10 +1083,10 @@ bool TreeSocket::ProcessLine(std::string &line)
                                        bool we_have_delta = (Instance->Time(false) != Instance->Time(true));
                                        time_t them = atoi(params[0].c_str());
                                        time_t delta = them - Instance->Time(false);
-                                       if ((delta < -300) || (delta > 300))
+                                       if ((delta < -600) || (delta > 600))
                                        {
                                                Instance->SNO->WriteToSnoMask('l',"\2ERROR\2: Your clocks are out by %d seconds (this is more than five minutes). Link aborted, \2PLEASE SYNC YOUR CLOCKS!\2",abs(delta));
-                                               WriteLine("ERROR :Your clocks are out by "+ConvToStr(abs(delta))+" seconds (this is more than ten minutes). Link aborted, PLEASE SYNC YOUR CLOCKS!");
+                                               SendError("Your clocks are out by "+ConvToStr(abs(delta))+" seconds (this is more than five minutes). Link aborted, PLEASE SYNC YOUR CLOCKS!");
                                                return false;
                                        }
                                        else if ((delta < -30) || (delta > 30))
@@ -1030,12 +1103,22 @@ bool TreeSocket::ProcessLine(std::string &line)
                                }
                                this->LinkState = CONNECTED;
                                Link* lnk = Utils->FindLink(InboundServerName);
-                               Node = new TreeServer(this->Utils,this->Instance, InboundServerName, InboundDescription, Utils->TreeRoot, this, lnk ? lnk->Hidden : false);
+
+                               Node = new TreeServer(this->Utils,this->Instance, InboundServerName, InboundDescription, InboundSID, Utils->TreeRoot, this, lnk ? lnk->Hidden : false);
+
+                               if (Node->DuplicateID())
+                               {
+                                       this->SendError("Server ID "+InboundSID+" already exists on the network!");
+                                       this->Instance->SNO->WriteToSnoMask('l',"Server \2"+InboundServerName+"\2 being introduced from \2" + prefix + "\2 denied, server ID already exists on the network. Closing link.");
+                                       return false;
+                               }
+                               Utils->DelBurstingServer(this);
                                Utils->TreeRoot->AddChild(Node);
                                params.clear();
                                params.push_back(InboundServerName);
                                params.push_back("*");
                                params.push_back("1");
+                               params.push_back(InboundSID);
                                params.push_back(":"+InboundDescription);
                                Utils->DoOneToAllButSender(Utils->TreeRoot->GetName(),"SERVER",params,InboundServerName);
                                this->bursting = true;
@@ -1052,7 +1135,7 @@ bool TreeSocket::ProcessLine(std::string &line)
 
                break;
                case LISTENER:
-                       this->WriteLine("ERROR :Internal error -- listening socket accepted its own descriptor!!!");
+                       this->SendError("Internal error -- listening socket accepted its own descriptor!!!");
                        return false;
                break;
                case CONNECTING:
@@ -1069,20 +1152,26 @@ bool TreeSocket::ProcessLine(std::string &line)
                        {
                                return this->Error(params);
                        }
+                       else if (command == "CAPAB")
+                       {
+                               return this->Capab(params);
+                       }
                break;
                case CONNECTED:
                        // This is the 'authenticated' state, when all passwords
                        // have been exchanged and anything past this point is taken
                        // as gospel.
 
-                       if (prefix != "")
+                       if (!prefix.empty())
                        {
                                std::string direction = prefix;
-                               userrec* t = this->Instance->FindNick(prefix);
+
+                               userrec *t = this->Instance->FindUUID(prefix);
                                if (t)
                                {
                                        direction = t->server;
                                }
+
                                TreeServer* route_back_again = Utils->BestRouteTo(direction);
                                if ((!route_back_again) || (route_back_again->GetSocket() != this))
                                {
@@ -1094,9 +1183,31 @@ bool TreeSocket::ProcessLine(std::string &line)
                                 * When there is activity on the socket, reset the ping counter so
                                 * that we're not wasting bandwidth pinging an active server.
                                 */
-                               route_back_again->SetNextPingTime(time(NULL) + 60);
+                               route_back_again->SetNextPingTime(time(NULL) + Utils->PingFreq);
                                route_back_again->SetPingFlag();
                        }
+                       else
+                       {
+                               prefix = this->GetName();
+                       }
+
+                       if ((command == "MODE") && (params.size() >= 2))
+                       {
+                               chanrec* channel = Instance->FindChan(params[0]);
+                               if (channel)
+                               {
+                                       userrec* x = Instance->FindNick(prefix);
+                                       if (x)
+                                       {
+                                               if (warned.find(x->server) == warned.end())
+                                               {
+                                                       Instance->Log(DEFAULT,"WARNING: I revceived modes '%s' from another server '%s'. This is not compliant with InspIRCd. Please check that server for bugs.", params[1].c_str(), x->server);
+                                                       Instance->SNO->WriteToSnoMask('d', "WARNING: The server %s is sending nonstandard modes: '%s MODE %s' where FMODE should be used, and may cause desyncs.", x->server, x->nick, params[1].c_str());
+                                                       warned[x->server] = x->nick;
+                                               }
+                                       }
+                               }
+                       }
 
                        if (command == "SVSMODE")
                        {
@@ -1106,16 +1217,19 @@ bool TreeSocket::ProcessLine(std::string &line)
                                 */
                                command = "MODE";
                        }
-                       std::string target = "";
+                       std::string target;
                        /* Yes, know, this is a mess. Its reasonably fast though as we're
                         * working with std::string here.
                         */
-                       if ((command == "NICK") && (params.size() >= 8))
+                       if (command == "UID")
                        {
-                               return this->IntroduceClient(prefix,params);
+                               return this->ParseUID(prefix, params);
                        }
                        else if (command == "FJOIN")
                        {
+                               TreeServer* ServerSource = Utils->FindServer(prefix);
+                               if (ServerSource)
+                                       Utils->SetRemoteBursting(ServerSource, false);
                                return this->ForceJoin(prefix,params);
                        }
                        else if (command == "STATS")
@@ -1126,6 +1240,10 @@ bool TreeSocket::ProcessLine(std::string &line)
                        {
                                return this->Motd(prefix, params);
                        }
+                       else if (command == "KILL" && Utils->IsServer(prefix))
+                       {
+                               return this->RemoteKill(prefix,params);
+                       }
                        else if (command == "MODULES")
                        {
                                return this->Modules(prefix, params);
@@ -1148,12 +1266,11 @@ bool TreeSocket::ProcessLine(std::string &line)
                        }
                        else if (command == "FMODE")
                        {
+                               TreeServer* ServerSource = Utils->FindServer(prefix);
+                               if (ServerSource)
+                                       Utils->SetRemoteBursting(ServerSource, false);
                                return this->ForceMode(prefix,params);
                        }
-                       else if (command == "KILL")
-                       {
-                               return this->RemoteKill(prefix,params);
-                       }
                        else if (command == "FTOPIC")
                        {
                                return this->ForceTopic(prefix,params);
@@ -1172,40 +1289,46 @@ bool TreeSocket::ProcessLine(std::string &line)
                        }
                        else if (command == "PING")
                        {
+                               if (prefix.empty())
+                                       prefix = this->GetName();
                                /*
                                 * We just got a ping from a server that's bursting.
                                 * This can't be right, so set them to not bursting, and
                                 * apply their lines.
                                 */
+                               TreeServer* ServerSource = Utils->FindServer(prefix);
+                               if (ServerSource)
+                                       Utils->SetRemoteBursting(ServerSource, false);
+
                                if (this->bursting)
                                {
                                        this->bursting = false;
                                        Instance->XLines->apply_lines(Utils->lines_to_apply);
                                        Utils->lines_to_apply = 0;
                                }
-                               if (prefix == "")
-                               {
-                                       prefix = this->GetName();
-                               }
+
                                return this->LocalPing(prefix,params);
                        }
                        else if (command == "PONG")
                        {
+                               if (prefix.empty())
+                                       prefix = this->GetName();
                                /*
                                 * We just got a pong from a server that's bursting.
                                 * This can't be right, so set them to not bursting, and
                                 * apply their lines.
                                 */
+                               TreeServer* ServerSource = Utils->FindServer(prefix);
+                               if (ServerSource)
+                                       Utils->SetRemoteBursting(ServerSource, false);
+
                                if (this->bursting)
                                {
                                        this->bursting = false;
                                        Instance->XLines->apply_lines(Utils->lines_to_apply);
                                        Utils->lines_to_apply = 0;
                                }
-                               if (prefix == "")
-                               {
-                                       prefix = this->GetName();
-                               }
+
                                return this->LocalPong(prefix,params);
                        }
                        else if (command == "VERSION")
@@ -1222,11 +1345,14 @@ bool TreeSocket::ProcessLine(std::string &line)
                        }
                        else if (command == "ADDLINE")
                        {
+                               TreeServer* ServerSource = Utils->FindServer(prefix);
+                               if (ServerSource)
+                                       Utils->SetRemoteBursting(ServerSource, false);
                                return this->AddLine(prefix,params);
                        }
                        else if (command == "SVSNICK")
                        {
-                               if (prefix == "")
+                               if (prefix.empty())
                                {
                                        prefix = this->GetName();
                                }
@@ -1236,10 +1362,6 @@ bool TreeSocket::ProcessLine(std::string &line)
                        {
                                return this->OperQuit(prefix,params);
                        }
-                       else if (command == "RSQUIT")
-                       {
-                               return this->RemoteSquit(prefix, params);
-                       }
                        else if (command == "IDLE")
                        {
                                return this->Whois(prefix,params);
@@ -1270,7 +1392,7 @@ bool TreeSocket::ProcessLine(std::string &line)
                                                        delete chan;
                                        }
                                }
-                               if (this->InboundServerName != "")
+                               if (!this->InboundServerName.empty())
                                {
                                        sourceserv = this->InboundServerName;
                                }
@@ -1278,7 +1400,7 @@ bool TreeSocket::ProcessLine(std::string &line)
                        }
                        else if (command == "SVSJOIN")
                        {
-                               if (prefix == "")
+                               if (prefix.empty())
                                {
                                        prefix = this->GetName();
                                }
@@ -1295,7 +1417,7 @@ bool TreeSocket::ProcessLine(std::string &line)
                        else if (command == "OPERNOTICE")
                        {
                                std::string sourceserv = this->myhost;
-                               if (this->InboundServerName != "")
+                               if (!this->InboundServerName.empty())
                                        sourceserv = this->InboundServerName;
                                if (params.size() >= 1)
                                        Instance->WriteOpers("*** From " + sourceserv + ": " + params[0]);
@@ -1304,7 +1426,7 @@ bool TreeSocket::ProcessLine(std::string &line)
                        else if (command == "MODENOTICE")
                        {
                                std::string sourceserv = this->myhost;
-                               if (this->InboundServerName != "")
+                               if (!this->InboundServerName.empty())
                                        sourceserv = this->InboundServerName;
                                if (params.size() >= 2)
                                {
@@ -1315,7 +1437,7 @@ bool TreeSocket::ProcessLine(std::string &line)
                        else if (command == "SNONOTICE")
                        {
                                std::string sourceserv = this->myhost;
-                               if (this->InboundServerName != "")
+                               if (!this->InboundServerName.empty())
                                        sourceserv = this->InboundServerName;
                                if (params.size() >= 2)
                                {
@@ -1329,10 +1451,8 @@ bool TreeSocket::ProcessLine(std::string &line)
                                Instance->XLines->apply_lines(Utils->lines_to_apply);
                                Utils->lines_to_apply = 0;
                                std::string sourceserv = this->myhost;
-                               if (this->InboundServerName != "")
-                               {
+                               if (!this->InboundServerName.empty())
                                        sourceserv = this->InboundServerName;
-                               }
                                this->Instance->SNO->WriteToSnoMask('l',"Received end of netburst from \2%s\2",sourceserv.c_str());
 
                                Event rmode((char*)sourceserv.c_str(), (Module*)Utils->Creator, "new_server");
@@ -1342,12 +1462,14 @@ bool TreeSocket::ProcessLine(std::string &line)
                        }
                        else
                        {
-                               // not a special inter-server command.
-                               // Emulate the actual user doing the command,
-                               // this saves us having a huge ugly parser.
-                               userrec* who = this->Instance->FindNick(prefix);
+                               /*
+                                * Not a special s2s command. Emulate the user doing it.
+                                * This saves us having a huge ugly command parser again.
+                                */
+                               userrec *who = this->Instance->FindUUID(prefix);
+
                                std::string sourceserv = this->myhost;
-                               if (this->InboundServerName != "")
+                               if (!this->InboundServerName.empty())
                                {
                                        sourceserv = this->InboundServerName;
                                }
@@ -1355,7 +1477,7 @@ bool TreeSocket::ProcessLine(std::string &line)
                                {
                                        if (Utils->IsServer(prefix))
                                        {
-                                               const char* modelist[127];
+                                               const char* modelist[MAXPARAMETERS];
                                                for (size_t i = 0; i < params.size(); i++)
                                                        modelist[i] = params[i].c_str();
                                                userrec* fake = new userrec(Instance);
@@ -1380,11 +1502,11 @@ bool TreeSocket::ProcessLine(std::string &line)
                                                {
                                                        std::deque<std::string> p;
                                                        p.push_back(params[0]);
-                                                       p.push_back("Nickname collision ("+prefix+" -> "+params[0]+")");
+                                                       p.push_back(":Nickname collision ("+prefix+" -> "+params[0]+")");
                                                        Utils->DoOneToMany(this->Instance->Config->ServerName,"KILL",p);
                                                        p.clear();
                                                        p.push_back(prefix);
-                                                       p.push_back("Nickname collision");
+                                                       p.push_back(":Nickname collision");
                                                        Utils->DoOneToMany(this->Instance->Config->ServerName,"KILL",p);
                                                        userrec::QuitUser(this->Instance,x,"Nickname collision ("+prefix+" -> "+params[0]+")");
                                                        userrec* y = this->Instance->FindNick(prefix);
@@ -1405,7 +1527,7 @@ bool TreeSocket::ProcessLine(std::string &line)
                                        switch (this->Instance->CallCommandHandler(command.c_str(), strparams, params.size(), who))
                                        {
                                                case CMD_INVALID:
-                                                       this->WriteLine("ERROR :Unrecognised command '"+std::string(command.c_str())+"' -- possibly loaded mismatched modules");
+                                                       this->SendError("Unrecognised command '"+std::string(command.c_str())+"' -- possibly loaded mismatched modules");
                                                        return false;
                                                break;
                                                case CMD_FAILURE:
@@ -1436,7 +1558,7 @@ bool TreeSocket::ProcessLine(std::string &line)
 std::string TreeSocket::GetName()
 {
        std::string sourceserv = this->myhost;
-       if (this->InboundServerName != "")
+       if (!this->InboundServerName.empty())
        {
                sourceserv = this->InboundServerName;
        }
@@ -1447,7 +1569,7 @@ void TreeSocket::OnTimeout()
 {
        if (this->LinkState == CONNECTING)
        {
-               this->Instance->SNO->WriteToSnoMask('l',"CONNECT: Connection to \002"+myhost+"\002 timed out.");
+               Utils->Creator->RemoteMessage(NULL, "CONNECT: Connection to \002%s\002 timed out.", myhost.c_str());
                Link* MyLink = Utils->FindLink(myhost);
                if (MyLink)
                        Utils->DoFailOver(MyLink);
@@ -1456,11 +1578,14 @@ void TreeSocket::OnTimeout()
 
 void TreeSocket::OnClose()
 {
+       if (this->LinkState == LISTENER)
+               return;
+
        // Connection closed.
        // If the connection is fully up (state CONNECTED)
        // then propogate a netsplit to all peers.
        std::string quitserver = this->myhost;
-       if (this->InboundServerName != "")
+       if (!this->InboundServerName.empty())
        {
                quitserver = this->InboundServerName;
        }
@@ -1470,8 +1595,13 @@ void TreeSocket::OnClose()
                Squit(s,"Remote host closed the connection");
        }
 
-       if (quitserver != "")
-               this->Instance->SNO->WriteToSnoMask('l',"Connection to '\2%s\2' failed.",quitserver.c_str());
+       if (!quitserver.empty())
+       {
+               Utils->Creator->RemoteMessage(NULL,"Connection to '\2%s\2' failed.",quitserver.c_str());
+               time_t server_uptime = Instance->Time() - this->age;    
+               if (server_uptime)
+                       Utils->Creator->RemoteMessage(NULL,"Connection to '\2%s\2' was established for %s", quitserver.c_str(), Utils->Creator->TimeToStr(server_uptime).c_str());
+       }
 }
 
 int TreeSocket::OnIncomingConnection(int newsock, char* ip)
@@ -1491,7 +1621,7 @@ int TreeSocket::OnIncomingConnection(int newsock, char* ip)
 
                if (!found)
                {
-                       this->Instance->SNO->WriteToSnoMask('l',"Server connection from %s denied (no link blocks with that IP address)", ip);
+                       Utils->Creator->RemoteMessage(NULL,"Server connection from %s denied (no link blocks with that IP address)", ip);
                        close(newsock);
                        return false;
                }