Do not add empty strings to outgoing lines. *needs testing, may break stuff*

[user/henk/code/inspircd.git] / src / modules / m_spanningtree / treesocket1.cpp

/*       +------------------------------------+
 *       | Inspire Internet Relay Chat Daemon |
 *       +------------------------------------+
 *
 *  InspIRCd: (C) 2002-2007 InspIRCd Development Team
 * See: http://www.inspircd.org/wiki/index.php/Credits
 *
 * This program is free but copyrighted software; see
 *            the file COPYING for details.
 *
 * ---------------------------------------------------
 */

#include "configreader.h"
#include "users.h"
#include "channels.h"
#include "modules.h"
#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"
#include "m_hash.h"
#include "socketengine.h"

#include "m_spanningtree/main.h"
#include "m_spanningtree/utils.h"
#include "m_spanningtree/treeserver.h"
#include "m_spanningtree/link.h"
#include "m_spanningtree/treesocket.h"
#include "m_spanningtree/resolvers.h"
#include "m_spanningtree/handshaketimer.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 m_hash.h */


/** Because most of the I/O gubbins are encapsulated within
 * InspSocket, we just call the superclass constructor for
 * most of the action, and append a few of our own values
 * to it.
 */
TreeSocket::TreeSocket(SpanningTreeUtilities* Util, InspIRCd* SI, std::string host, int port, bool listening, unsigned long maxtime, Module* HookMod)
        : InspSocket(SI, host, port, listening, maxtime), Utils(Util), Hook(HookMod)
{
        myhost = host;
        this->LinkState = LISTENER;
        theirchallenge = ourchallenge = "";
        if (listening && Hook)
                InspSocketHookRequest(this, (Module*)Utils->Creator, Hook).Send();
}

TreeSocket::TreeSocket(SpanningTreeUtilities* Util, InspIRCd* SI, std::string host, int port, bool listening, unsigned long maxtime, const std::string &ServerName, const std::string &bindto, Module* HookMod)
        : InspSocket(SI, host, port, listening, maxtime, bindto), Utils(Util), Hook(HookMod)
{
        myhost = ServerName;
        theirchallenge = ourchallenge = "";
        this->LinkState = CONNECTING;
        if (Hook)
                InspSocketHookRequest(this, (Module*)Utils->Creator, Hook).Send();
}

/** When a listening socket gives us a new file descriptor,
 * we must associate it with a socket without creating a new
 * connection. This constructor is used for this purpose.
 */
TreeSocket::TreeSocket(SpanningTreeUtilities* Util, InspIRCd* SI, int newfd, char* ip, Module* HookMod)
        : InspSocket(SI, newfd, ip), Utils(Util), Hook(HookMod)
{
        this->LinkState = WAIT_AUTH_1;
        theirchallenge = ourchallenge = "";
        /* If we have a transport module hooked to the parent, hook the same module to this
         * socket, and set a timer waiting for handshake before we send CAPAB etc.
         */
        if (Hook)
                InspSocketHookRequest(this, (Module*)Utils->Creator, Hook).Send();

        Instance->Timers->AddTimer(new HandshakeTimer(Instance, this, &(Utils->LinkBlocks[0]), this->Utils, 1));
}

ServerState TreeSocket::GetLinkState()
{
        return this->LinkState;
}

Module* TreeSocket::GetHook()
{
        return this->Hook;
}

TreeSocket::~TreeSocket()
{
        if (Hook)
                InspSocketUnhookRequest(this, (Module*)Utils->Creator, Hook).Send();

        Utils->DelBurstingServer(this);
}

const std::string& TreeSocket::GetOurChallenge()
{
        return this->ourchallenge;
}

void TreeSocket::SetOurChallenge(const std::string &c)
{
        this->ourchallenge = c;
}

const std::string& TreeSocket::GetTheirChallenge()
{
        return this->theirchallenge;
}

void TreeSocket::SetTheirChallenge(const std::string &c)
{
        this->theirchallenge = c;
}

std::string TreeSocket::MakePass(const std::string &password, const std::string &challenge)
{
        /* This is a simple (maybe a bit hacky?) HMAC algorithm, thanks to jilles for
         * suggesting the use of HMAC to secure the password against various attacks.
         *
         * Note: If m_sha256.so is not loaded, we MUST fall back to plaintext with no
         *       HMAC challenge/response.
         */
        Module* sha256 = Instance->FindModule("m_sha256.so");
        if (Utils->ChallengeResponse && sha256 && !challenge.empty())
        {
                /* XXX: This is how HMAC is supposed to be done:
                 *
                 * sha256( (pass xor 0x5c) + sha256((pass xor 0x36) + m) )
                 *
                 * Note that we are encoding the hex hash, not the binary
                 * output of the hash which is slightly different to standard.
                 *
                 * Don't ask me why its always 0x5c and 0x36... it just is.
                 */
                std::string hmac1, hmac2;

                for (size_t n = 0; n < password.length(); n++)
                {
                        hmac1 += static_cast<char>(password[n] ^ 0x5C);
                        hmac2 += static_cast<char>(password[n] ^ 0x36);
                }

                hmac2 += challenge;
                HashResetRequest(Utils->Creator, sha256).Send();
                hmac2 = HashSumRequest(Utils->Creator, sha256, hmac2).Send();

                HashResetRequest(Utils->Creator, sha256).Send();
                std::string hmac = hmac1 + hmac2;
                hmac = HashSumRequest(Utils->Creator, sha256, hmac).Send();

                return "HMAC-SHA256:"+ hmac;
        }
        else if (!challenge.empty() && !sha256)
                Instance->Log(DEFAULT,"Not authenticating to server using SHA256/HMAC because we don't have m_sha256 loaded!");

        return password;
}

/** When an outbound connection finishes connecting, we receive
 * this event, and must send our SERVER string to the other
 * side. If the other side is happy, as outlined in the server
 * to server docs on the inspircd.org site, the other side
 * will then send back its own server string.
 */
bool TreeSocket::OnConnected()
{
        if (this->LinkState == CONNECTING)
        {
                /* we do not need to change state here. */
                for (std::vector<Link>::iterator x = Utils->LinkBlocks.begin(); x < Utils->LinkBlocks.end(); x++)
                {
                        if (x->Name == this->myhost)
                        {
                                this->Instance->SNO->WriteToSnoMask('l',"Connection to \2"+myhost+"\2["+(x->HiddenFromStats ? "<hidden>" : this->GetIP())+"] started.");
                                if (Hook)
                                {
                                        InspSocketHookRequest(this, (Module*)Utils->Creator, Hook).Send();
                                        this->Instance->SNO->WriteToSnoMask('l',"Connection to \2"+myhost+"\2["+(x->HiddenFromStats ? "<hidden>" : this->GetIP())+"] using transport \2"+x->Hook+"\2");
                                }
                                this->OutboundPass = x->SendPass;

                                /* found who we're supposed to be connecting to, send the neccessary gubbins. */
                                if (this->GetHook())
                                        Instance->Timers->AddTimer(new HandshakeTimer(Instance, this, &(*x), this->Utils, 1));
                                else
                                        this->SendCapabilities();

                                return true;
                        }
                }
        }
        /* There is a (remote) chance that between the /CONNECT and the connection
         * being accepted, some muppet has removed the <link> block and rehashed.
         * If that happens the connection hangs here until it's closed. Unlikely
         * and rather harmless.
         */
        this->Instance->SNO->WriteToSnoMask('l',"Connection to \2"+myhost+"\2 lost link tag(!)");
        return true;
}

void TreeSocket::OnError(InspSocketError e)
{
        /* We don't handle this method, because all our
         * dirty work is done in OnClose() (see below)
         * which is still called on error conditions too.
         */
        if (e == I_ERR_CONNECT)
        {
                this->Instance->SNO->WriteToSnoMask('l',"Connection failed: Connection to \002"+myhost+"\002 refused");
                Link* MyLink = Utils->FindLink(myhost);
                if (MyLink)
                        Utils->DoFailOver(MyLink);
        }
}

int TreeSocket::OnDisconnect()
{
        /* For the same reason as above, we don't
         * handle OnDisconnect()
         */
        return true;
}

/** Recursively send the server tree with distances as hops.
 * This is used during network burst to inform the other server
 * (and any of ITS servers too) of what servers we know about.
 * If at any point any of these servers already exist on the other
 * end, our connection may be terminated. The hopcounts given
 * by this function are relative, this doesn't matter so long as
 * they are all >1, as all the remote servers re-calculate them
 * to be relative too, with themselves as hop 0.
 */
void TreeSocket::SendServers(TreeServer* Current, TreeServer* s, int hops)
{
        char command[1024];
        for (unsigned int q = 0; q < Current->ChildCount(); q++)
        {
                TreeServer* recursive_server = Current->GetChild(q);
                if (recursive_server != s)
                {
                        snprintf(command,1024,":%s SERVER %s * %d :%s",Current->GetName().c_str(),recursive_server->GetName().c_str(),hops,recursive_server->GetDesc().c_str());
                        this->WriteLine(command);
                        this->WriteLine(":"+recursive_server->GetName()+" VERSION :"+recursive_server->GetVersion());
                        /* down to next level */
                        this->SendServers(recursive_server, s, hops+1);
                }
        }
}

std::string TreeSocket::MyCapabilities()
{
        std::vector<std::string> modlist;
        std::string capabilities = "";
        for (int i = 0; i <= this->Instance->GetModuleCount(); i++)
        {
                if (this->Instance->modules[i]->GetVersion().Flags & VF_COMMON)
                        modlist.push_back(this->Instance->Config->module_names[i]);
        }
        sort(modlist.begin(),modlist.end());
        for (unsigned int i = 0; i < modlist.size(); i++)
        {
                if (i)
                        capabilities = capabilities + ",";
                capabilities = capabilities + modlist[i];
        }
        return capabilities;
}

std::string TreeSocket::RandString(unsigned int length)
{
        char* randombuf = new char[length+1];
        std::string out;
        int fd = open("/dev/urandom", O_RDONLY, 0);

        if (fd >= 0)
        {
                read(fd, randombuf, length);
                close(fd);
        }
        else
        {
                for (unsigned int i = 0; i < length; i++)
                        randombuf[i] = rand();
        }

        for (unsigned int i = 0; i < length; i++)
        {
                char randchar = static_cast<char>((randombuf[i] & 0x7F) | 0x21);
                out += (randchar == '=' ? '_' : randchar);
        }

        delete[] randombuf;
        return out;
}

void TreeSocket::SendCapabilities()
{
        irc::commasepstream modulelist(MyCapabilities());
        this->WriteLine("CAPAB START");

        /* Send module names, split at 509 length */
        std::string item = "*";
        std::string line = "CAPAB MODULES ";
        while ((item = modulelist.GetToken()) != "")
        {
                if (line.length() + item.length() + 1 > 509)
                {
                        this->WriteLine(line);
                        line = "CAPAB MODULES ";
                }

                if (line != "CAPAB MODULES ")
                        line.append(",");

                line.append(item);
        }
        if (line != "CAPAB MODULES ")
                this->WriteLine(line);

        int ip6 = 0;
        int ip6support = 0;
#ifdef IPV6
        ip6 = 1;
#endif
#ifdef SUPPORT_IP6LINKS
        ip6support = 1;
#endif
        std::string extra;
        /* Do we have sha256 available? If so, we send a challenge */
        if (Utils->ChallengeResponse && (Instance->FindModule("m_sha256.so")))
        {
                this->SetOurChallenge(RandString(20));
                extra = " CHALLENGE=" + this->GetOurChallenge();
        }

        this->WriteLine("CAPAB CAPABILITIES :NICKMAX="+ConvToStr(NICKMAX)+" HALFOP="+ConvToStr(this->Instance->Config->AllowHalfop)+" CHANMAX="+ConvToStr(CHANMAX)+" MAXMODES="+ConvToStr(MAXMODES)+" IDENTMAX="+ConvToStr(IDENTMAX)+" MAXQUIT="+ConvToStr(MAXQUIT)+" MAXTOPIC="+ConvToStr(MAXTOPIC)+" MAXKICK="+ConvToStr(MAXKICK)+" MAXGECOS="+ConvToStr(MAXGECOS)+" MAXAWAY="+ConvToStr(MAXAWAY)+" IP6NATIVE="+ConvToStr(ip6)+" IP6SUPPORT="+ConvToStr(ip6support)+" PROTOCOL="+ConvToStr(ProtocolVersion)+extra);

        this->WriteLine("CAPAB END");
}

/* Check a comma seperated list for an item */
bool TreeSocket::HasItem(const std::string &list, const std::string &item)
{
        irc::commasepstream seplist(list);
        std::string item2 = "*";
        while ((item2 = seplist.GetToken()) != "")
        {
                if (item2 == item)
                        return true;
        }
        return false;
}

/* Isolate and return the elements that are different between two comma seperated lists */
std::string TreeSocket::ListDifference(const std::string &one, const std::string &two)
{
        irc::commasepstream list_one(one);
        std::string item = "*";
        std::string result = "";
        while ((item = list_one.GetToken()) != "")
        {
                if (!HasItem(two, item))
                {
                        result.append(" ");
                        result.append(item);
                }
        }
        return result;
}

bool TreeSocket::Capab(const std::deque<std::string> &params)
{
        if (params.size() < 1)
        {
                this->WriteLine("ERROR :Invalid number of parameters for CAPAB - Mismatched version");
                return false;
        }
        if (params[0] == "START")
        {
                this->ModuleList = "";
                this->CapKeys.clear();
        }
        else if (params[0] == "END")
        {
                std::string reason = "";
                int ip6support = 0;
#ifdef SUPPORT_IP6LINKS
                ip6support = 1;
#endif
                /* Compare ModuleList and check CapKeys...
                 * Maybe this could be tidier? -- Brain
                 */
                if ((this->ModuleList != this->MyCapabilities()) && (this->ModuleList.length()))
                {
                        std::string diff = ListDifference(this->ModuleList, this->MyCapabilities());
                        if (!diff.length())
                        {
                                diff = "your server:" + ListDifference(this->MyCapabilities(), this->ModuleList);
                        }
                        else
                        {
                                diff = "this server:" + diff;
                        }
                        if (diff.length() == 12)
                                reason = "Module list in CAPAB is not alphabetically ordered, cannot compare lists.";
                        else
                                reason = "Modules loaded on these servers are not correctly matched, these modules are not loaded on " + diff;
                }
                if (((this->CapKeys.find("IP6SUPPORT") == this->CapKeys.end()) && (ip6support)) || ((this->CapKeys.find("IP6SUPPORT") != this->CapKeys.end()) && (this->CapKeys.find("IP6SUPPORT")->second != ConvToStr(ip6support))))
                        reason = "We don't both support linking to IPV6 servers";
                if (((this->CapKeys.find("IP6NATIVE") != this->CapKeys.end()) && (this->CapKeys.find("IP6NATIVE")->second == "1")) && (!ip6support))
                        reason = "The remote server is IPV6 native, and we don't support linking to IPV6 servers";
                if (((this->CapKeys.find("NICKMAX") == this->CapKeys.end()) || ((this->CapKeys.find("NICKMAX") != this->CapKeys.end()) && (this->CapKeys.find("NICKMAX")->second != ConvToStr(NICKMAX)))))
                        reason = "Maximum nickname lengths differ or remote nickname length not specified";
                if (((this->CapKeys.find("PROTOCOL") == this->CapKeys.end()) || ((this->CapKeys.find("PROTOCOL") != this->CapKeys.end()) && (this->CapKeys.find("PROTOCOL")->second != ConvToStr(ProtocolVersion)))))
                {
                        if (this->CapKeys.find("PROTOCOL") != this->CapKeys.end())
                        {
                                reason = "Mismatched protocol versions "+this->CapKeys.find("PROTOCOL")->second+" and "+ConvToStr(ProtocolVersion);
                        }
                        else
                        {
                                reason = "Protocol version not specified";
                        }
                }
                if (((this->CapKeys.find("HALFOP") == this->CapKeys.end()) && (Instance->Config->AllowHalfop)) || ((this->CapKeys.find("HALFOP") != this->CapKeys.end()) && (this->CapKeys.find("HALFOP")->second != ConvToStr(Instance->Config->AllowHalfop))))
                        reason = "We don't both have halfop support enabled/disabled identically";
                if (((this->CapKeys.find("IDENTMAX") == this->CapKeys.end()) || ((this->CapKeys.find("IDENTMAX") != this->CapKeys.end()) && (this->CapKeys.find("IDENTMAX")->second != ConvToStr(IDENTMAX)))))
                        reason = "Maximum ident lengths differ or remote ident length not specified";
                if (((this->CapKeys.find("CHANMAX") == this->CapKeys.end()) || ((this->CapKeys.find("CHANMAX") != this->CapKeys.end()) && (this->CapKeys.find("CHANMAX")->second != ConvToStr(CHANMAX)))))
                        reason = "Maximum channel lengths differ or remote channel length not specified";
                if (((this->CapKeys.find("MAXMODES") == this->CapKeys.end()) || ((this->CapKeys.find("MAXMODES") != this->CapKeys.end()) && (this->CapKeys.find("MAXMODES")->second != ConvToStr(MAXMODES)))))
                        reason = "Maximum modes per line differ or remote modes per line not specified";
                if (((this->CapKeys.find("MAXQUIT") == this->CapKeys.end()) || ((this->CapKeys.find("MAXQUIT") != this->CapKeys.end()) && (this->CapKeys.find("MAXQUIT")->second != ConvToStr(MAXQUIT)))))
                        reason = "Maximum quit lengths differ or remote quit length not specified";
                if (((this->CapKeys.find("MAXTOPIC") == this->CapKeys.end()) || ((this->CapKeys.find("MAXTOPIC") != this->CapKeys.end()) && (this->CapKeys.find("MAXTOPIC")->second != ConvToStr(MAXTOPIC)))))
                        reason = "Maximum topic lengths differ or remote topic length not specified";
                if (((this->CapKeys.find("MAXKICK") == this->CapKeys.end()) || ((this->CapKeys.find("MAXKICK") != this->CapKeys.end()) && (this->CapKeys.find("MAXKICK")->second != ConvToStr(MAXKICK)))))
                        reason = "Maximum kick lengths differ or remote kick length not specified";
                if (((this->CapKeys.find("MAXGECOS") == this->CapKeys.end()) || ((this->CapKeys.find("MAXGECOS") != this->CapKeys.end()) && (this->CapKeys.find("MAXGECOS")->second != ConvToStr(MAXGECOS)))))
                        reason = "Maximum GECOS (fullname) lengths differ or remote GECOS length not specified";
                if (((this->CapKeys.find("MAXAWAY") == this->CapKeys.end()) || ((this->CapKeys.find("MAXAWAY") != this->CapKeys.end()) && (this->CapKeys.find("MAXAWAY")->second != ConvToStr(MAXAWAY)))))
                        reason = "Maximum awaymessage lengths differ or remote awaymessage length not specified";

                /* Challenge response, store their challenge for our password */
                std::map<std::string,std::string>::iterator n = this->CapKeys.find("CHALLENGE");
                if (Utils->ChallengeResponse && (n != this->CapKeys.end()) && (Instance->FindModule("m_sha256.so")))
                {
                        /* Challenge-response is on now */
                        this->SetTheirChallenge(n->second);
                        if (!this->GetTheirChallenge().empty() && (this->LinkState == CONNECTING))
                        {
                                this->WriteLine(std::string("SERVER ")+this->Instance->Config->ServerName+" "+this->MakePass(OutboundPass, this->GetTheirChallenge())+" 0 :"+this->Instance->Config->ServerDesc);
                        }
                }
                else
                {
                        /* They didnt specify a challenge or we don't have m_sha256.so, we use plaintext */
                        if (this->LinkState == CONNECTING)
                                this->WriteLine(std::string("SERVER ")+this->Instance->Config->ServerName+" "+OutboundPass+" 0 :"+this->Instance->Config->ServerDesc);
                }

                if (reason.length())
                {
                        this->WriteLine("ERROR :CAPAB negotiation failed: "+reason);
                        return false;
                }
        }
        else if ((params[0] == "MODULES") && (params.size() == 2))
        {
                if (!this->ModuleList.length())
                {
                        this->ModuleList.append(params[1]);
                }
                else
                {
                        this->ModuleList.append(",");
                        this->ModuleList.append(params[1]);
                }
        }

        else if ((params[0] == "CAPABILITIES") && (params.size() == 2))
        {
                irc::tokenstream capabs(params[1]);
                std::string item;
                bool more = true;
                while ((more = capabs.GetToken(item)))
                {
                        /* Process each key/value pair */
                        std::string::size_type equals = item.rfind('=');
                        if (equals != std::string::npos)
                        {
                                std::string var = item.substr(0, equals);
                                std::string value = item.substr(equals+1, item.length());
                                CapKeys[var] = value;
                        }
                }
        }
        return true;
}

/** This function forces this server to quit, removing this server
 * and any users on it (and servers and users below that, etc etc).
 * It's very slow and pretty clunky, but luckily unless your network
 * is having a REAL bad hair day, this function shouldnt be called
 * too many times a month ;-)
 */
void TreeSocket::SquitServer(std::string &from, TreeServer* Current)
{
        /* recursively squit the servers attached to 'Current'.
         * We're going backwards so we don't remove users
         * while we still need them ;)
         */
        for (unsigned int q = 0; q < Current->ChildCount(); q++)
        {
                TreeServer* recursive_server = Current->GetChild(q);
                this->SquitServer(from,recursive_server);
        }
        /* Now we've whacked the kids, whack self */
        num_lost_servers++;
        num_lost_users += Current->QuitUsers(from);
}

/** This is a wrapper function for SquitServer above, which
 * does some validation first and passes on the SQUIT to all
 * other remaining servers.
 */
void TreeSocket::Squit(TreeServer* Current, const std::string &reason)
{
        if ((Current) && (Current != Utils->TreeRoot))
        {
                Event rmode((char*)Current->GetName().c_str(), (Module*)Utils->Creator, "lost_server");
                rmode.Send(Instance);

                std::deque<std::string> params;
                params.push_back(Current->GetName());
                params.push_back(":"+reason);
                Utils->DoOneToAllButSender(Current->GetParent()->GetName(),"SQUIT",params,Current->GetName());
                if (Current->GetParent() == Utils->TreeRoot)
                {
                        this->Instance->WriteOpers("Server \002"+Current->GetName()+"\002 split: "+reason);
                }
                else
                {
                        this->Instance->WriteOpers("Server \002"+Current->GetName()+"\002 split from server \002"+Current->GetParent()->GetName()+"\002 with reason: "+reason);
                }
                num_lost_servers = 0;
                num_lost_users = 0;
                std::string from = Current->GetParent()->GetName()+" "+Current->GetName();
                SquitServer(from, Current);
                Current->Tidy();
                Current->GetParent()->DelChild(Current);
                DELETE(Current);
                this->Instance->WriteOpers("Netsplit complete, lost \002%d\002 users on \002%d\002 servers.", num_lost_users, num_lost_servers);
        }
        else
        {
                Instance->Log(DEFAULT,"Squit from unknown server");
        }
}

/** FMODE command - server mode with timestamp checks */
bool TreeSocket::ForceMode(const std::string &source, std::deque<std::string> &params)
{
        /* Chances are this is a 1.0 FMODE without TS */
        if (params.size() < 3)
        {
                /* No modes were in the command, probably a channel with no modes set on it */
                return true;
        }

        bool smode = false;
        std::string sourceserv;
        /* Are we dealing with an FMODE from a user, or from a server? */
        userrec* who = this->Instance->FindNick(source);
        if (who)
        {
                /* FMODE from a user, set sourceserv to the users server name */
                sourceserv = who->server;
        }
        else
        {
                /* FMODE from a server, create a fake user to receive mode feedback */
                who = new userrec(this->Instance);
                who->SetFd(FD_MAGIC_NUMBER);
                smode = true;      /* Setting this flag tells us we should free the userrec later */
                sourceserv = source;    /* Set sourceserv to the actual source string */
        }
        const char* modelist[64];
        time_t TS = 0;
        int n = 0;
        memset(&modelist,0,sizeof(modelist));
        for (unsigned int q = 0; (q < params.size()) && (q < 64); q++)
        {
                if (q == 1)
                {
                        /* The timestamp is in this position.
                         * We don't want to pass that up to the
                         * server->client protocol!
                         */
                        TS = atoi(params[q].c_str());
                }
                else
                {
                        /* Everything else is fine to append to the modelist */
                        modelist[n++] = params[q].c_str();
                }

        }
        /* Extract the TS value of the object, either userrec or chanrec */
        userrec* dst = this->Instance->FindNick(params[0]);
        chanrec* chan = NULL;
        time_t ourTS = 0;
        if (dst)
        {
                ourTS = dst->age;
        }
        else
        {
                chan = this->Instance->FindChan(params[0]);
                if (chan)
                {
                        ourTS = chan->age;
                }
                else
                        /* Oops, channel doesnt exist! */
                        return true;
        }

        /* TS is equal or less: Merge the mode changes into ours and pass on.
         */
        if (TS <= ourTS)
        {
                if (smode)
                {
                        this->Instance->SendMode(modelist, n, who);
                }
                else
                {
                        this->Instance->CallCommandHandler("MODE", modelist, n, who);
                }
                /* HOT POTATO! PASS IT ON! */
                Utils->DoOneToAllButSender(source,"FMODE",params,sourceserv);
        }
        /* If the TS is greater than ours, we drop the mode and dont pass it anywhere.
         */

        if (smode)
                DELETE(who);

        return true;
}

/** FTOPIC command */
bool TreeSocket::ForceTopic(const std::string &source, std::deque<std::string> &params)
{
        if (params.size() != 4)
                return true;
        time_t ts = atoi(params[1].c_str());
        std::string nsource = source;
        chanrec* c = this->Instance->FindChan(params[0]);
        if (c)
        {
                if ((ts >= c->topicset) || (!*c->topic))
                {
                        std::string oldtopic = c->topic;
                        strlcpy(c->topic,params[3].c_str(),MAXTOPIC);
                        strlcpy(c->setby,params[2].c_str(),127);
                        c->topicset = ts;
                        /* if the topic text is the same as the current topic,
                         * dont bother to send the TOPIC command out, just silently
                         * update the set time and set nick.
                         */
                        if (oldtopic != params[3])
                        {
                                userrec* user = this->Instance->FindNick(source);
                                if (!user)
                                {
                                        c->WriteChannelWithServ(source.c_str(), "TOPIC %s :%s", c->name, c->topic);
                                }
                                else
                                {
                                        c->WriteChannel(user, "TOPIC %s :%s", c->name, c->topic);
                                        nsource = user->server;
                                }
                                /* all done, send it on its way */
                                params[3] = ":" + params[3];
                                Utils->DoOneToAllButSender(source,"FTOPIC",params,nsource);
                        }
                }

        }
        return true;
}

/** FJOIN, similar to TS6 SJOIN, but not quite. */
bool TreeSocket::ForceJoin(const std::string &source, std::deque<std::string> &params)
{
        /* 1.1 FJOIN works as follows:
         *
         * Each FJOIN is sent along with a timestamp, and the side with the lowest
         * timestamp 'wins'. From this point on we will refer to this side as the
         * winner. The side with the higher timestamp loses, from this point on we
         * will call this side the loser or losing side. This should be familiar to
         * anyone who's dealt with dreamforge or TS6 before.
         *
         * When two sides of a split heal and this occurs, the following things
         * will happen:
         *
         * If the timestamps are exactly equal, both sides merge their privilages
         * and users, as in InspIRCd 1.0 and ircd2.8. The channels have not been
         * re-created during a split, this is safe to do.
         *
         *
         * If the timestamps are NOT equal, the losing side removes all privilage
         * modes from all of its users that currently exist in the channel, before
         * introducing new users into the channel which are listed in the FJOIN
         * command's parameters. This means, all modes +ohv, and privilages added
         * by modules, such as +qa. The losing side then LOWERS its timestamp value
         * of the channel to match that of the winning side, and the modes of the
         * users of the winning side are merged in with the losing side. The loser
         * then sends out a set of FMODE commands which 'confirm' that it just
         * removed all privilage modes from its existing users, which allows for
         * services packages to still work correctly without needing to know the
         * timestamping rules which InspIRCd follows. In TS6 servers this is always
         * a problem, and services packages must contain code which explicitly
         * behaves as TS6 does, removing ops from the losing side of a split where
         * neccessary within its internal records, as this state information is
         * not explicitly echoed out in that protocol.
         *
         * The winning side on the other hand will ignore all user modes from the
         * losing side, so only its own modes get applied. Life is simple for those
         * who succeed at internets. :-)
         *
         * NOTE: Unlike TS6 and dreamforge and other protocols which have SJOIN,
         * FJOIN does not contain the simple-modes such as +iklmnsp. Why not,
         * you ask? Well, quite simply because we don't need to. They'll be sent
         * after the FJOIN by FMODE, and FMODE is timestamped, so in the event
         * the losing side sends any modes for the channel which shouldnt win,
         * they wont as their timestamp will be too high :-)
         */

        if (params.size() < 3)
                return true;

        char first[MAXBUF];          /* The first parameter of the mode command */
        char modestring[MAXBUF];        /* The mode sequence (2nd parameter) of the mode command */
        char* mode_users[127];    /* The values used by the mode command */
        memset(&mode_users,0,sizeof(mode_users));       /* Initialize mode parameters */
        mode_users[0] = first;    /* Set this up to be our on-stack value */
        mode_users[1] = modestring;     /* Same here as above */
        strcpy(modestring,"+");  /* Initialize the mode sequence to just '+' */
        unsigned int modectr = 2;       /* Pointer to the third mode parameter (e.g. the one after the +-sequence) */

        userrec* who = NULL;                /* User we are currently checking */
        std::string channel = params[0];        /* Channel name, as a string */
        time_t TS = atoi(params[1].c_str());    /* Timestamp given to us for remote side */
        std::string nicklist = params[2];
        bool created = false;

        /* Try and find the channel */
        chanrec* chan = this->Instance->FindChan(channel);

        /* Initialize channel name in the mode parameters */
        strlcpy(mode_users[0],channel.c_str(),MAXBUF);

        /* default TS is a high value, which if we dont have this
         * channel will let the other side apply their modes.
         */
        time_t ourTS = Instance->Time(true)+600;
        /* Does this channel exist? if it does, get its REAL timestamp */
        if (chan)
                ourTS = chan->age;
        else
                created = true; /* don't perform deops, and set TS to correct time after processing. */

        /* do this first, so our mode reversals are correctly received by other servers
         * if there is a TS collision.
         */
        params[2] = ":" + params[2];
        Utils->DoOneToAllButSender(source,"FJOIN",params,source);

        /* In 1.1, if they have the newer channel, we immediately clear
         * all status modes from our users. We then accept their modes.
         * If WE have the newer channel its the other side's job to do this.
         * Note that this causes the losing server to send out confirming
         * FMODE lines.
         */
        if (ourTS > TS)
        {
                std::deque<std::string> param_list;
                /* Lower the TS here */
                if (Utils->AnnounceTSChange && chan)
                        chan->WriteChannelWithServ(Instance->Config->ServerName,
                        "NOTICE %s :TS for %s changed from %lu to %lu", chan->name, chan->name, ourTS, TS);
                ourTS = TS;
                /* Zap all the privilage modes on our side, if the channel exists here */
                if (!created)
                {
                        param_list.push_back(channel);
                        /* Do this first! */
                        chan->age = TS;
                        this->RemoveStatus(Instance->Config->ServerName, param_list);
                }
        }
        /* Put the final parameter of the FJOIN into a tokenstream ready to split it */
        irc::tokenstream users(nicklist);
        std::string item;

        /* Now, process every 'prefixes,nick' pair */
        while (users.GetToken(item))
        {
                /* Find next user */
                const char* usr = item.c_str();
                /* Safety check just to make sure someones not sent us an FJOIN full of spaces
                 * (is this even possible?) */
                if (usr && *usr)
                {
                        const char* permissions = usr;
                        int ntimes = 0;
                        char* nm = new char[MAXBUF];
                        char* tnm = nm;
                        /* Iterate through all the prefix values, convert them from prefixes
                         * to mode letters, and append them to the mode sequence
                         */
                        while ((*permissions) && (*permissions != ',') && (ntimes < MAXBUF))
                        {
                                ModeHandler* mh = Instance->Modes->FindPrefix(*permissions);
                                if (mh)
                                {
                                        /* This is a valid prefix */
                                        ntimes++;
                                        *tnm++ = mh->GetModeChar();
                                }
                                else
                                {
                                        /* Not a valid prefix...
                                         * danger bill bobbertson! (that's will robinsons older brother ;-) ...)
                                         */
                                        this->Instance->WriteOpers("ERROR: We received a user with an unknown prefix '%c'. Closed connection to avoid a desync.",*permissions);
                                        this->WriteLine(std::string("ERROR :Invalid prefix '")+(*permissions)+"' in FJOIN");
                                        return false;
                                }
                                usr++;
                                permissions++;
                        }
                        /* Null terminate modes */
                        *tnm = 0;
                        /* Advance past the comma, to the nick */
                        usr++;
                        /* Check the user actually exists */
                        who = this->Instance->FindNick(usr);
                        if (who)
                        {
                                /* Check that the user's 'direction' is correct
                                 * based on the server sending the FJOIN. We must
                                 * check each nickname in turn, because the origin of
                                 * the FJOIN may be different to the origin of the nicks
                                 * in the command itself.
                                 */
                                TreeServer* route_back_again = Utils->BestRouteTo(who->server);
                                if ((!route_back_again) || (route_back_again->GetSocket() != this))
                                {
                                        /* Oh dear oh dear. */
                                        delete[] nm;
                                        continue;
                                }

                                /* NOTE: Moved this below the fake direction check, so that modes
                                 * arent put into the mode list for users that were collided, and
                                 * may reconnect from the other side or our side before the split
                                 * is completed!
                                 */

                                /* Did they get any modes? How many times? */
                                strlcat(modestring, nm, MAXBUF);
                                for (int k = 0; k < ntimes; k++)
                                        mode_users[modectr++] = strdup(usr);
                                /* Free temporary buffer used for mode sequence */
                                delete[] nm;

                                /* Finally, we can actually place the user into the channel.
                                 * We're sure its right. Final answer, phone a friend.
                                 */
                                if (created)
                                        chanrec::JoinUser(this->Instance, who, channel.c_str(), true, "", TS);
                                else
                                        chanrec::JoinUser(this->Instance, who, channel.c_str(), true, "");
                                /* Have we already queued up MAXMODES modes with parameters
                                 * (+qaohv) ready to be sent to the server?
                                 */
                                if (modectr >= (MAXMODES-1))
                                {
                                        /* Only actually give the users any status if we lost
                                         * the FJOIN or drew (equal timestamps).
                                         * It isn't actually possible for ourTS to be > TS here,
                                         * only possible to actually have ourTS == TS, or
                                         * ourTS < TS, because if we lost, we already lowered
                                         * our TS above before we entered this loop. We only
                                         * check >= as a safety measure, in case someone stuffed
                                         * up. If someone DID stuff up, it was most likely me.
                                         * Note: I do not like baseball bats in the face...
                                         */
                                        if (ourTS >= TS)
                                        {
                                                this->Instance->SendMode((const char**)mode_users,modectr,who);

                                                /* Something stuffed up, and for some reason, the timestamp is
                                                 * NOT lowered right now and should be. Lower it. Usually this
                                                 * code won't be executed, doubtless someone will remove it some
                                                 * day soon.
                                                 */
                                                if (ourTS > TS)
                                                {
                                                        Instance->Log(DEFAULT,"Channel TS for %s changed from %lu to %lu",chan->name,ourTS,TS);
                                                        chan->age = TS;
                                                        ourTS = TS;
                                                }
                                        }

                                        /* Reset all this back to defaults, and
                                         * free any ram we have left allocated.
                                         */
                                        strcpy(mode_users[1],"+");
                                        for (unsigned int f = 2; f < modectr; f++)
                                                free(mode_users[f]);
                                        modectr = 2;
                                }
                        }
                        else
                        {
                                /* Remember to free this */
                                delete[] nm;
                                /* If we got here, there's a nick in FJOIN which doesnt exist on this server.
                                 * We don't try to process the nickname here (that WOULD cause a segfault because
                                 * we'd be playing with null pointers) however, we DO pass the nickname on, just
                                 * in case somehow we're desynched, so that other users which might be able to see
                                 * the nickname get their fair chance to process it.
                                 */
                                Instance->Log(SPARSE,"Warning! Invalid user %s in FJOIN to channel %s IGNORED", usr, channel.c_str());
                                continue;
                        }
                }
        }

        /* there werent enough modes built up to flush it during FJOIN,
         * or, there are a number left over. flush them out.
         */
        if ((modectr > 2) && (who) && (chan))
        {
                if (ourTS >= TS)
                {
                        /* Our channel is newer than theirs. Evil deeds must be afoot. */
                        this->Instance->SendMode((const char**)mode_users,modectr,who);
                        /* Yet again, we can't actually get a true value here, if everything else
                         * is working as it should.
                         */
                        if (ourTS > TS)
                        {
                                Instance->Log(DEFAULT,"Channel TS for %s changed from %lu to %lu",chan->name,ourTS,TS);
                                chan->age = TS;
                                ourTS = TS;
                        }
                }

                /* Free anything we have left to free */
                for (unsigned int f = 2; f < modectr; f++)
                        free(mode_users[f]);
        }
        /* All done. That wasnt so bad was it, you can wipe
         * the sweat from your forehead now. :-)
         */
        return true;
}

/** NICK command */
bool TreeSocket::IntroduceClient(const std::string &source, std::deque<std::string> &params)
{
        /** Do we have enough parameters:
         * NICK age nick host dhost ident +modes ip :gecos
         */
        if (params.size() != 8)
        {
                this->WriteLine(std::string(":")+this->Instance->Config->ServerName+" KILL "+params[1]+" :Invalid client introduction ("+params[1]+"?)");
                return true;
        }

        time_t age = atoi(params[0].c_str());
        const char* tempnick = params[1].c_str();

        /** Check parameters for validity before introducing the client, discovered by dmb.
         * XXX: Can we make this neater?
         */
        if (!age)
        {
                this->WriteLine(std::string(":")+this->Instance->Config->ServerName+" KILL "+params[1]+" :Invalid client introduction (Invalid TS?)");
                return true;
        }
        else if (params[1].length() > NICKMAX)
        {
                this->WriteLine(std::string(":")+this->Instance->Config->ServerName+" KILL "+params[1]+" :Invalid client introduction ("+params[1]+" > NICKMAX?)");
                return true;
        }
        else if (params[2].length() > 64)
        {
                this->WriteLine(std::string(":")+this->Instance->Config->ServerName+" KILL "+params[1]+" :Invalid client introduction ("+params[2]+" > 64?)");
                return true;
        }
        else if (params[3].length() > 64)
        {
                this->WriteLine(std::string(":")+this->Instance->Config->ServerName+" KILL "+params[1]+" :Invalid client introduction ("+params[3]+" > 64?)");
                return true;
        }
        else if (params[4].length() > IDENTMAX)
        {
                this->WriteLine(std::string(":")+this->Instance->Config->ServerName+" KILL "+params[1]+" :Invalid client introduction ("+params[4]+" > IDENTMAX?)");
                return true;
        }
        else if (params[7].length() > MAXGECOS)
        {
                this->WriteLine(std::string(":")+this->Instance->Config->ServerName+" KILL "+params[1]+" :Invalid client introduction ("+params[7]+" > MAXGECOS?)");
                return true;
        }

        /** Our client looks ok, lets introduce it now
         */
        Instance->Log(DEBUG,"New remote client %s",tempnick);
        user_hash::iterator iter = this->Instance->clientlist->find(tempnick);

        if (iter != this->Instance->clientlist->end())
        {
                /* nick collision */
                this->WriteLine(std::string(":")+this->Instance->Config->ServerName+" KILL "+tempnick+" :Nickname collision");
                userrec::QuitUser(this->Instance, iter->second, "Nickname collision");
                return true;
        }

        userrec* _new = new userrec(this->Instance);
        (*(this->Instance->clientlist))[tempnick] = _new;
        _new->SetFd(FD_MAGIC_NUMBER);
        strlcpy(_new->nick, tempnick,NICKMAX-1);
        strlcpy(_new->host, params[2].c_str(),63);
        strlcpy(_new->dhost, params[3].c_str(),63);
        _new->server = this->Instance->FindServerNamePtr(source.c_str());
        strlcpy(_new->ident, params[4].c_str(),IDENTMAX);
        strlcpy(_new->fullname, params[7].c_str(),MAXGECOS);
        _new->registered = REG_ALL;
        _new->signon = age;

        /* we need to remove the + from the modestring, so we can do our stuff */
        std::string::size_type pos_after_plus = params[5].find_first_not_of('+');
        if (pos_after_plus != std::string::npos)
        params[5] = params[5].substr(pos_after_plus);

        for (std::string::iterator v = params[5].begin(); v != params[5].end(); v++)
        {
                _new->modes[(*v)-65] = 1;
                /* For each mode thats set, increase counter */
                ModeHandler* mh = Instance->Modes->FindMode(*v, MODETYPE_USER);
                if (mh)
                        mh->ChangeCount(1);
        }

        /* now we've done with modes processing, put the + back for remote servers */
        params[5] = "+" + params[5];

#ifdef SUPPORT_IP6LINKS
        if (params[6].find_first_of(":") != std::string::npos)
                _new->SetSockAddr(AF_INET6, params[6].c_str(), 0);
        else
#endif
                _new->SetSockAddr(AF_INET, params[6].c_str(), 0);

        Instance->AddGlobalClone(_new);

        if (!this->Instance->SilentULine(_new->server))
                this->Instance->SNO->WriteToSnoMask('C',"Client connecting at %s: %s!%s@%s [%s]",_new->server,_new->nick,_new->ident,_new->host, _new->GetIPString());

        params[7] = ":" + params[7];
        Utils->DoOneToAllButSender(source,"NICK", params, source);

        // Increment the Source Servers User Count..
        TreeServer* SourceServer = Utils->FindServer(source);
        if (SourceServer)
        {
                SourceServer->AddUserCount();
        }

        FOREACH_MOD_I(Instance,I_OnPostConnect,OnPostConnect(_new));

        return true;
}

/** Send one or more FJOINs for a channel of users.
 * If the length of a single line is more than 480-NICKMAX
 * in length, it is split over multiple lines.
 */
void TreeSocket::SendFJoins(TreeServer* Current, chanrec* c)
{
        std::string buffer;
        char list[MAXBUF];
        std::string individual_halfops = std::string(":")+this->Instance->Config->ServerName+" FMODE "+c->name+" "+ConvToStr(c->age);

        size_t dlen, curlen;
        dlen = curlen = snprintf(list,MAXBUF,":%s FJOIN %s %lu",this->Instance->Config->ServerName,c->name,(unsigned long)c->age);
        int numusers = 0;
        char* ptr = list + dlen;

        CUList *ulist = c->GetUsers();
        std::string modes = "";
        std::string params = "";

        for (CUList::iterator i = ulist->begin(); i != ulist->end(); i++)
        {
                // The first parameter gets a : before it
                size_t ptrlen = snprintf(ptr, MAXBUF, " %s%s,%s", !numusers ? ":" : "", c->GetAllPrefixChars(i->second), i->second->nick);

                curlen += ptrlen;
                ptr += ptrlen;

                numusers++;

                if (curlen > (480-NICKMAX))
                {
                        buffer.append(list).append("\r\n");
                        dlen = curlen = snprintf(list,MAXBUF,":%s FJOIN %s %lu",this->Instance->Config->ServerName,c->name,(unsigned long)c->age);
                        ptr = list + dlen;
                        ptrlen = 0;
                        numusers = 0;
                }
        }

        if (numusers)
                buffer.append(list).append("\r\n");

        /* Sorry for the hax. Because newly created channels assume +nt,
         * if this channel doesnt have +nt, explicitly send -n and -t for the missing modes.
         */
        bool inverted = false;
        if (!c->IsModeSet('n'))
        {
                modes.append("-n");
                inverted = true;
        }
        if (!c->IsModeSet('t'))
        {
                modes.append("-t");
                inverted = true;
        }
        if (inverted)
        {
                modes.append("+");
        }

        buffer.append(":").append(this->Instance->Config->ServerName).append(" FMODE ").append(c->name).append(" ").append(ConvToStr(c->age)).append(" +").append(c->ChanModes(true)).append("\r\n");

        int linesize = 1;
        for (BanList::iterator b = c->bans.begin(); b != c->bans.end(); b++)
        {
                int size = strlen(b->data) + 2;
                int currsize = linesize + size;
                if (currsize <= 350)
                {
                        modes.append("b");
                        params.append(" ").append(b->data);
                        linesize += size; 
                }
                if ((params.length() >= MAXMODES) || (currsize > 350))
                {
                        /* Wrap at MAXMODES */
                        buffer.append(":").append(this->Instance->Config->ServerName).append(" FMODE ").append(c->name).append(" ").append(ConvToStr(c->age)).append(" +").append(modes).append(params).append("\r\n");
                        modes = "";
                        params = "";
                        linesize = 1;
                }
        }

        /* Only send these if there are any */
        if (!modes.empty())
                buffer.append(":").append(this->Instance->Config->ServerName).append(" FMODE ").append(c->name).append(" ").append(ConvToStr(c->age)).append(" +").append(modes).append(params);

        this->WriteLine(buffer);
}

/** Send G, Q, Z and E lines */
void TreeSocket::SendXLines(TreeServer* Current)
{
        char data[MAXBUF];
        std::string buffer;
        std::string n = this->Instance->Config->ServerName;
        const char* sn = n.c_str();
        /* Yes, these arent too nice looking, but they get the job done */
        for (std::vector<ZLine*>::iterator i = Instance->XLines->zlines.begin(); i != Instance->XLines->zlines.end(); i++)
        {
                snprintf(data,MAXBUF,":%s ADDLINE Z %s %s %lu %lu :%s\r\n",sn,(*i)->ipaddr,(*i)->source,(unsigned long)(*i)->set_time,(unsigned long)(*i)->duration,(*i)->reason);
                buffer.append(data);
        }
        for (std::vector<QLine*>::iterator i = Instance->XLines->qlines.begin(); i != Instance->XLines->qlines.end(); i++)
        {
                snprintf(data,MAXBUF,":%s ADDLINE Q %s %s %lu %lu :%s\r\n",sn,(*i)->nick,(*i)->source,(unsigned long)(*i)->set_time,(unsigned long)(*i)->duration,(*i)->reason);
                buffer.append(data);
        }
        for (std::vector<GLine*>::iterator i = Instance->XLines->glines.begin(); i != Instance->XLines->glines.end(); i++)
        {
                snprintf(data,MAXBUF,":%s ADDLINE G %s@%s %s %lu %lu :%s\r\n",sn,(*i)->identmask,(*i)->hostmask,(*i)->source,(unsigned long)(*i)->set_time,(unsigned long)(*i)->duration,(*i)->reason);
                buffer.append(data);
        }
        for (std::vector<ELine*>::iterator i = Instance->XLines->elines.begin(); i != Instance->XLines->elines.end(); i++)
        {
                snprintf(data,MAXBUF,":%s ADDLINE E %s@%s %s %lu %lu :%s\r\n",sn,(*i)->identmask,(*i)->hostmask,(*i)->source,(unsigned long)(*i)->set_time,(unsigned long)(*i)->duration,(*i)->reason);
                buffer.append(data);
        }
        for (std::vector<ZLine*>::iterator i = Instance->XLines->pzlines.begin(); i != Instance->XLines->pzlines.end(); i++)
        {
                snprintf(data,MAXBUF,":%s ADDLINE Z %s %s %lu %lu :%s\r\n",sn,(*i)->ipaddr,(*i)->source,(unsigned long)(*i)->set_time,(unsigned long)(*i)->duration,(*i)->reason);
                buffer.append(data);
        }
        for (std::vector<QLine*>::iterator i = Instance->XLines->pqlines.begin(); i != Instance->XLines->pqlines.end(); i++)
        {
                snprintf(data,MAXBUF,":%s ADDLINE Q %s %s %lu %lu :%s\r\n",sn,(*i)->nick,(*i)->source,(unsigned long)(*i)->set_time,(unsigned long)(*i)->duration,(*i)->reason);
                buffer.append(data);
        }
        for (std::vector<GLine*>::iterator i = Instance->XLines->pglines.begin(); i != Instance->XLines->pglines.end(); i++)
        {
                snprintf(data,MAXBUF,":%s ADDLINE G %s@%s %s %lu %lu :%s\r\n",sn,(*i)->identmask,(*i)->hostmask,(*i)->source,(unsigned long)(*i)->set_time,(unsigned long)(*i)->duration,(*i)->reason);
                buffer.append(data);
        }
        for (std::vector<ELine*>::iterator i = Instance->XLines->pelines.begin(); i != Instance->XLines->pelines.end(); i++)
        {
                snprintf(data,MAXBUF,":%s ADDLINE E %s@%s %s %lu %lu :%s\r\n",sn,(*i)->identmask,(*i)->hostmask,(*i)->source,(unsigned long)(*i)->set_time,(unsigned long)(*i)->duration,(*i)->reason);
                buffer.append(data);
        }

        if (!buffer.empty())
                this->WriteLine(buffer);
}

/** Send channel modes and topics */
void TreeSocket::SendChannelModes(TreeServer* Current)
{
        char data[MAXBUF];
        std::deque<std::string> list;
        std::string n = this->Instance->Config->ServerName;
        const char* sn = n.c_str();
        for (chan_hash::iterator c = this->Instance->chanlist->begin(); c != this->Instance->chanlist->end(); c++)
        {
                SendFJoins(Current, c->second);
                if (*c->second->topic)
                {
                        snprintf(data,MAXBUF,":%s FTOPIC %s %lu %s :%s",sn,c->second->name,(unsigned long)c->second->topicset,c->second->setby,c->second->topic);
                        this->WriteLine(data);
                }
                FOREACH_MOD_I(this->Instance,I_OnSyncChannel,OnSyncChannel(c->second,(Module*)Utils->Creator,(void*)this));
                list.clear();
                c->second->GetExtList(list);
                for (unsigned int j = 0; j < list.size(); j++)
                {
                        FOREACH_MOD_I(this->Instance,I_OnSyncChannelMetaData,OnSyncChannelMetaData(c->second,(Module*)Utils->Creator,(void*)this,list[j]));
                }
        }
}

/** send all users and their oper state/modes */
void TreeSocket::SendUsers(TreeServer* Current)
{
        char data[MAXBUF];
        std::deque<std::string> list;
        std::string dataline;
        for (user_hash::iterator u = this->Instance->clientlist->begin(); u != this->Instance->clientlist->end(); u++)
        {
                if (u->second->registered == REG_ALL)
                {
                        snprintf(data,MAXBUF,":%s NICK %lu %s %s %s %s +%s %s :%s",u->second->server,(unsigned long)u->second->age,u->second->nick,u->second->host,u->second->dhost,u->second->ident,u->second->FormatModes(),u->second->GetIPString(),u->second->fullname);
                        this->WriteLine(data);
                        if (*u->second->oper)
                        {
                                snprintf(data,MAXBUF,":%s OPERTYPE %s", u->second->nick, u->second->oper);
                                this->WriteLine(data);
                        }
                        if (*u->second->awaymsg)
                        {
                                snprintf(data,MAXBUF,":%s AWAY :%s", u->second->nick, u->second->awaymsg);
                                this->WriteLine(data);
                        }
                        FOREACH_MOD_I(this->Instance,I_OnSyncUser,OnSyncUser(u->second,(Module*)Utils->Creator,(void*)this));
                        list.clear();
                        u->second->GetExtList(list);

                        for (unsigned int j = 0; j < list.size(); j++)
                        {
                                FOREACH_MOD_I(this->Instance,I_OnSyncUserMetaData,OnSyncUserMetaData(u->second,(Module*)Utils->Creator,(void*)this,list[j]));
                        }
                }
        }
}

/** This function is called when we want to send a netburst to a local
 * server. There is a set order we must do this, because for example
 * users require their servers to exist, and channels require their
 * users to exist. You get the idea.
 */
void TreeSocket::DoBurst(TreeServer* s)
{
        std::string name = s->GetName();
        std::string burst = "BURST "+ConvToStr(Instance->Time(true));
        std::string endburst = "ENDBURST";
        this->Instance->SNO->WriteToSnoMask('l',"Bursting to \2%s\2 (Authentication: %s).", name.c_str(), this->GetTheirChallenge().empty() ? "plaintext password" : "SHA256-HMAC challenge-response");
        this->WriteLine(burst);
        /* send our version string */
        this->WriteLine(std::string(":")+this->Instance->Config->ServerName+" VERSION :"+this->Instance->GetVersionString());
        /* Send server tree */
        this->SendServers(Utils->TreeRoot,s,1);
        /* Send users and their oper status */
        this->SendUsers(s);
        /* Send everything else (channel modes, xlines etc) */
        this->SendChannelModes(s);
        this->SendXLines(s);
        FOREACH_MOD_I(this->Instance,I_OnSyncOtherMetaData,OnSyncOtherMetaData((Module*)Utils->Creator,(void*)this));
        this->WriteLine(endburst);
        this->Instance->SNO->WriteToSnoMask('l',"Finished bursting to \2"+name+"\2.");
}

/** This function is called when we receive data from a remote
 * server. We buffer the data in a std::string (it doesnt stay
 * there for long), reading using InspSocket::Read() which can
 * read up to 16 kilobytes in one operation.
 *
 * IF THIS FUNCTION RETURNS FALSE, THE CORE CLOSES AND DELETES
 * THE SOCKET OBJECT FOR US.
 */
bool TreeSocket::OnDataReady()
{
        char* data = this->Read();
        /* Check that the data read is a valid pointer and it has some content */
        if (data && *data)
        {
                this->in_buffer.append(data);
                /* While there is at least one new line in the buffer,
                 * do something useful (we hope!) with it.
                 */
                while (in_buffer.find("\n") != std::string::npos)
                {
                        std::string ret = in_buffer.substr(0,in_buffer.find("\n")-1);
                        in_buffer = in_buffer.substr(in_buffer.find("\n")+1,in_buffer.length()-in_buffer.find("\n"));
                        /* Use rfind here not find, as theres more
                         * chance of the \r being near the end of the
                         * string, not the start.
                         */
                        if (ret.find("\r") != std::string::npos)
                                ret = in_buffer.substr(0,in_buffer.find("\r")-1);
                        /* Process this one, abort if it
                         * didnt return true.
                         */
                        if (!this->ProcessLine(ret))
                        {
                                return false;
                        }
                }
                return true;
        }
        /* EAGAIN returns an empty but non-NULL string, so this
         * evaluates to TRUE for EAGAIN but to FALSE for EOF.
         */
        return (data && !*data);
}