[user/henk/code/inspircd.git] / src / users.cpp

/*
 * InspIRCd -- Internet Relay Chat Daemon
 *
 *   Copyright (C) 2009-2010 Daniel De Graaf <danieldg@inspircd.org>
 *   Copyright (C) 2006-2009 Robin Burchell <robin+git@viroteck.net>
 *   Copyright (C) 2006-2007, 2009 Dennis Friis <peavey@inspircd.org>
 *   Copyright (C) 2008 John Brooks <john.brooks@dereferenced.net>
 *   Copyright (C) 2008 Thomas Stagner <aquanight@inspircd.org>
 *   Copyright (C) 2008 Oliver Lupton <oliverlupton@gmail.com>
 *   Copyright (C) 2003-2008 Craig Edwards <craigedwards@brainbox.cc>
 *
 * This file is part of InspIRCd.  InspIRCd is free software: you can
 * redistribute it and/or modify it under the terms of the GNU General Public
 * License as published by the Free Software Foundation, version 2.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */


#include "inspircd.h"
#include "xline.h"

bool User::IsNoticeMaskSet(unsigned char sm)
{
        if (!isalpha(sm))
                return false;
        return (snomasks[sm-65]);
}

bool User::IsModeSet(unsigned char m) const
{
        ModeHandler* mh = ServerInstance->Modes->FindMode(m, MODETYPE_USER);
        return (mh && modes[mh->GetId()]);
}

std::string User::GetModeLetters(bool includeparams) const
{
        std::string ret(1, '+');
        std::string params;

        for (unsigned char i = 'A'; i < 'z'; i++)
        {
                const ModeHandler* const mh = ServerInstance->Modes.FindMode(i, MODETYPE_USER);
                if ((!mh) || (!IsModeSet(mh)))
                        continue;

                ret.push_back(mh->GetModeChar());
                if ((includeparams) && (mh->NeedsParam(true)))
                {
                        const std::string val = mh->GetUserParameter(this);
                        if (!val.empty())
                                params.append(1, ' ').append(val);
                }
        }

        ret += params;
        return ret;
}

User::User(const std::string& uid, Server* srv, UserType type)
        : age(ServerInstance->Time())
        , signon(0)
        , uuid(uid)
        , server(srv)
        , registered(REG_NONE)
        , quitting(false)
        , usertype(type)
{
        client_sa.sa.sa_family = AF_UNSPEC;

        ServerInstance->Logs->Log("USERS", LOG_DEBUG, "New UUID for user: %s", uuid.c_str());

        // Do not insert FakeUsers into the uuidlist so FindUUID() won't return them which is the desired behavior
        if (type != USERTYPE_SERVER)
        {
                if (!ServerInstance->Users.uuidlist.insert(std::make_pair(uuid, this)).second)
                        throw CoreException("Duplicate UUID in User constructor: " + uuid);
        }
}

LocalUser::LocalUser(int myfd, irc::sockets::sockaddrs* client, irc::sockets::sockaddrs* servaddr)
        : User(ServerInstance->UIDGen.GetUID(), ServerInstance->FakeClient->server, USERTYPE_LOCAL)
        , eh(this)
        , bytes_in(0)
        , bytes_out(0)
        , cmds_in(0)
        , cmds_out(0)
        , quitting_sendq(false)
        , lastping(true)
        , exempt(false)
        , nping(0)
        , idle_lastmsg(0)
        , CommandFloodPenalty(0)
        , already_sent(0)
{
        signon = ServerInstance->Time();
        // The user's default nick is their UUID
        nick = uuid;
        ident = "unknown";
        eh.SetFd(myfd);
        memcpy(&client_sa, client, sizeof(irc::sockets::sockaddrs));
        memcpy(&server_sa, servaddr, sizeof(irc::sockets::sockaddrs));
        ChangeRealHost(GetIPString(), true);
}

User::~User()
{
}

const std::string& User::MakeHost()
{
        if (!this->cached_makehost.empty())
                return this->cached_makehost;

        // XXX: Is there really a need to cache this?
        this->cached_makehost = ident + "@" + GetRealHost();
        return this->cached_makehost;
}

const std::string& User::MakeHostIP()
{
        if (!this->cached_hostip.empty())
                return this->cached_hostip;

        // XXX: Is there really a need to cache this?
        this->cached_hostip = ident + "@" + this->GetIPString();
        return this->cached_hostip;
}

const std::string& User::GetFullHost()
{
        if (!this->cached_fullhost.empty())
                return this->cached_fullhost;

        // XXX: Is there really a need to cache this?
        this->cached_fullhost = nick + "!" + ident + "@" + GetDisplayedHost();
        return this->cached_fullhost;
}

const std::string& User::GetFullRealHost()
{
        if (!this->cached_fullrealhost.empty())
                return this->cached_fullrealhost;

        // XXX: Is there really a need to cache this?
        this->cached_fullrealhost = nick + "!" + ident + "@" + GetRealHost();
        return this->cached_fullrealhost;
}

bool User::HasModePermission(const ModeHandler* mh) const
{
        return true;
}

bool LocalUser::HasModePermission(const ModeHandler* mh) const
{
        if (!this->IsOper())
                return false;

        const unsigned char mode = mh->GetModeChar();
        if (mode < 'A' || mode > ('A' + 64)) return false;

        return ((mh->GetModeType() == MODETYPE_USER ? oper->AllowedUserModes : oper->AllowedChanModes))[(mode - 'A')];

}
/*
 * users on remote servers can completely bypass all permissions based checks.
 * This prevents desyncs when one server has different type/class tags to another.
 * That having been said, this does open things up to the possibility of source changes
 * allowing remote kills, etc - but if they have access to the src, they most likely have
 * access to the conf - so it's an end to a means either way.
 */
bool User::HasPermission(const std::string&)
{
        return true;
}

bool LocalUser::HasPermission(const std::string &command)
{
        // are they even an oper at all?
        if (!this->IsOper())
        {
                return false;
        }

        return oper->AllowedOperCommands.Contains(command);
}

bool User::HasPrivPermission(const std::string &privstr, bool noisy)
{
        return true;
}

bool LocalUser::HasPrivPermission(const std::string &privstr, bool noisy)
{
        if (!this->IsOper())
        {
                if (noisy)
                        this->WriteNotice("You are not an oper");
                return false;
        }

        if (oper->AllowedPrivs.Contains(privstr))
                return true;

        if (noisy)
                this->WriteNotice("Oper type " + oper->name + " does not have access to priv " + privstr);

        return false;
}

void UserIOHandler::OnDataReady()
{
        if (user->quitting)
                return;

        if (recvq.length() > user->MyClass->GetRecvqMax() && !user->HasPrivPermission("users/flood/increased-buffers"))
        {
                ServerInstance->Users->QuitUser(user, "RecvQ exceeded");
                ServerInstance->SNO->WriteToSnoMask('a', "User %s RecvQ of %lu exceeds connect class maximum of %lu",
                        user->nick.c_str(), (unsigned long)recvq.length(), user->MyClass->GetRecvqMax());
                return;
        }

        unsigned long sendqmax = ULONG_MAX;
        if (!user->HasPrivPermission("users/flood/increased-buffers"))
                sendqmax = user->MyClass->GetSendqSoftMax();

        unsigned long penaltymax = ULONG_MAX;
        if (!user->HasPrivPermission("users/flood/no-fakelag"))
                penaltymax = user->MyClass->GetPenaltyThreshold() * 1000;

        // The maximum size of an IRC message minus the terminating CR+LF.
        const size_t maxmessage = ServerInstance->Config->Limits.MaxLine - 2;
        std::string line;
        line.reserve(maxmessage);

        bool eol_found;
        std::string::size_type qpos;

        while (user->CommandFloodPenalty < penaltymax && getSendQSize() < sendqmax)
        {
                qpos = 0;
                eol_found = false;

                const size_t qlen = recvq.length();
                while (qpos < qlen)
                {
                        char c = recvq[qpos++];
                        switch (c)
                        {
                                case '\0':
                                        c = ' ';
                                        break;
                                case '\r':
                                        continue;
                                case '\n':
                                        eol_found = true;
                                        break;
                        }

                        if (eol_found)
                                break;

                        if (line.length() < maxmessage)
                                line.push_back(c);
                }

                // if we return here, we haven't found a newline and make no modifications to recvq
                // so we can wait for more data
                if (!eol_found)
                        return;

                // just found a newline. Terminate the string, and pull it out of recvq
                recvq.erase(0, qpos);

                // TODO should this be moved to when it was inserted in recvq?
                ServerInstance->stats.Recv += qpos;
                user->bytes_in += qpos;
                user->cmds_in++;

                ServerInstance->Parser.ProcessBuffer(line, user);
                if (user->quitting)
                        return;

                // clear() does not reclaim memory associated with the string, so our .reserve() call is safe
                line.clear();
        }

        if (user->CommandFloodPenalty >= penaltymax && !user->MyClass->fakelag)
                ServerInstance->Users->QuitUser(user, "Excess Flood");
}

void UserIOHandler::AddWriteBuf(const std::string &data)
{
        if (user->quitting_sendq)
                return;
        if (!user->quitting && getSendQSize() + data.length() > user->MyClass->GetSendqHardMax() &&
                !user->HasPrivPermission("users/flood/increased-buffers"))
        {
                user->quitting_sendq = true;
                ServerInstance->GlobalCulls.AddSQItem(user);
                return;
        }

        // We still want to append data to the sendq of a quitting user,
        // e.g. their ERROR message that says 'closing link'

        WriteData(data);
}

void UserIOHandler::OnError(BufferedSocketError)
{
        ServerInstance->Users->QuitUser(user, getError());
}

CullResult User::cull()
{
        if (!quitting)
                ServerInstance->Users->QuitUser(this, "Culled without QuitUser");

        if (client_sa.family() != AF_UNSPEC)
                ServerInstance->Users->RemoveCloneCounts(this);

        return Extensible::cull();
}

CullResult LocalUser::cull()
{
        eh.cull();
        return User::cull();
}

CullResult FakeUser::cull()
{
        // Fake users don't quit, they just get culled.
        quitting = true;
        // Fake users are not inserted into UserManager::clientlist or uuidlist, so we don't need to modify those here
        return User::cull();
}

void User::Oper(OperInfo* info)
{
        ModeHandler* opermh = ServerInstance->Modes->FindMode('o', MODETYPE_USER);
        if (this->IsModeSet(opermh))
                this->UnOper();

        this->SetMode(opermh, true);
        this->oper = info;
        this->WriteCommand("MODE", "+o");
        FOREACH_MOD(OnOper, (this, info->name));

        std::string opername;
        if (info->oper_block)
                opername = info->oper_block->getString("name");

        if (IS_LOCAL(this))
        {
                LocalUser* l = IS_LOCAL(this);
                std::string vhost = oper->getConfig("vhost");
                if (!vhost.empty())
                        l->ChangeDisplayedHost(vhost);
                std::string opClass = oper->getConfig("class");
                if (!opClass.empty())
                        l->SetClass(opClass);
        }

        ServerInstance->SNO->WriteToSnoMask('o',"%s (%s@%s) is now an IRC operator of type %s (using oper '%s')",
                nick.c_str(), ident.c_str(), GetRealHost().c_str(), oper->name.c_str(), opername.c_str());
        this->WriteNumeric(RPL_YOUAREOPER, InspIRCd::Format("You are now %s %s", strchr("aeiouAEIOU", oper->name[0]) ? "an" : "a", oper->name.c_str()));

        ServerInstance->Logs->Log("OPER", LOG_DEFAULT, "%s opered as type: %s", GetFullRealHost().c_str(), oper->name.c_str());
        ServerInstance->Users->all_opers.push_back(this);

        // Expand permissions from config for faster lookup
        if (IS_LOCAL(this))
                oper->init();

        FOREACH_MOD(OnPostOper, (this, oper->name, opername));
}

void OperInfo::init()
{
        AllowedOperCommands.Clear();
        AllowedPrivs.Clear();
        AllowedUserModes.reset();
        AllowedChanModes.reset();
        AllowedUserModes['o' - 'A'] = true; // Call me paranoid if you want.

        for(std::vector<reference<ConfigTag> >::iterator iter = class_blocks.begin(); iter != class_blocks.end(); ++iter)
        {
                ConfigTag* tag = *iter;

                AllowedOperCommands.AddList(tag->getString("commands"));
                AllowedPrivs.AddList(tag->getString("privs"));

                std::string modes = tag->getString("usermodes");
                for (std::string::const_iterator c = modes.begin(); c != modes.end(); ++c)
                {
                        if (*c == '*')
                        {
                                this->AllowedUserModes.set();
                        }
                        else if (*c >= 'A' && *c <= 'z')
                        {
                                this->AllowedUserModes[*c - 'A'] = true;
                        }
                }

                modes = tag->getString("chanmodes");
                for (std::string::const_iterator c = modes.begin(); c != modes.end(); ++c)
                {
                        if (*c == '*')
                        {
                                this->AllowedChanModes.set();
                        }
                        else if (*c >= 'A' && *c <= 'z')
                        {
                                this->AllowedChanModes[*c - 'A'] = true;
                        }
                }
        }
}

void User::UnOper()
{
        if (!this->IsOper())
                return;

        /*
         * unset their oper type (what IS_OPER checks).
         * note, order is important - this must come before modes as -o attempts
         * to call UnOper. -- w00t
         */
        oper = NULL;


        /* Remove all oper only modes from the user when the deoper - Bug #466*/
        Modes::ChangeList changelist;
        const ModeParser::ModeHandlerMap& usermodes = ServerInstance->Modes->GetModes(MODETYPE_USER);
        for (ModeParser::ModeHandlerMap::const_iterator i = usermodes.begin(); i != usermodes.end(); ++i)
        {
                ModeHandler* mh = i->second;
                if (mh->NeedsOper())
                        changelist.push_remove(mh);
        }

        ServerInstance->Modes->Process(this, NULL, this, changelist);

        // Remove the user from the oper list
        stdalgo::vector::swaperase(ServerInstance->Users->all_opers, this);

        ModeHandler* opermh = ServerInstance->Modes->FindMode('o', MODETYPE_USER);
        this->SetMode(opermh, false);
        FOREACH_MOD(OnPostDeoper, (this));
}

/*
 * Check class restrictions
 */
void LocalUser::CheckClass(bool clone_count)
{
        ConnectClass* a = this->MyClass;

        if (!a)
        {
                ServerInstance->Users->QuitUser(this, "Access denied by configuration");
                return;
        }
        else if (a->type == CC_DENY)
        {
                ServerInstance->Users->QuitUser(this, a->config->getString("reason", "Unauthorised connection"));
                return;
        }
        else if (clone_count)
        {
                const UserManager::CloneCounts& clonecounts = ServerInstance->Users->GetCloneCounts(this);
                if ((a->GetMaxLocal()) && (clonecounts.local > a->GetMaxLocal()))
                {
                        ServerInstance->Users->QuitUser(this, "No more connections allowed from your host via this connect class (local)");
                        if (a->maxconnwarn)
                                ServerInstance->SNO->WriteToSnoMask('a', "WARNING: maximum LOCAL connections (%ld) exceeded for IP %s", a->GetMaxLocal(), this->GetIPString().c_str());
                        return;
                }
                else if ((a->GetMaxGlobal()) && (clonecounts.global > a->GetMaxGlobal()))
                {
                        ServerInstance->Users->QuitUser(this, "No more connections allowed from your host via this connect class (global)");
                        if (a->maxconnwarn)
                                ServerInstance->SNO->WriteToSnoMask('a', "WARNING: maximum GLOBAL connections (%ld) exceeded for IP %s", a->GetMaxGlobal(), this->GetIPString().c_str());
                        return;
                }
        }

        this->nping = ServerInstance->Time() + a->GetPingTime();
}

bool LocalUser::CheckLines(bool doZline)
{
        const char* check[] = { "G" , "K", (doZline) ? "Z" : NULL, NULL };

        if (!this->exempt)
        {
                for (int n = 0; check[n]; ++n)
                {
                        XLine *r = ServerInstance->XLines->MatchesLine(check[n], this);

                        if (r)
                        {
                                r->Apply(this);
                                return true;
                        }
                }
        }

        return false;
}

void LocalUser::FullConnect()
{
        ServerInstance->stats.Connects++;
        this->idle_lastmsg = ServerInstance->Time();

        /*
         * You may be thinking "wtf, we checked this in User::AddClient!" - and yes, we did, BUT.
         * At the time AddClient is called, we don't have a resolved host, by here we probably do - which
         * may put the user into a totally seperate class with different restrictions! so we *must* check again.
         * Don't remove this! -- w00t
         */
        MyClass = NULL;
        SetClass();
        CheckClass();
        CheckLines();

        if (quitting)
                return;

        this->WriteNumeric(RPL_WELCOME, InspIRCd::Format("Welcome to the %s IRC Network %s", ServerInstance->Config->Network.c_str(), GetFullRealHost().c_str()));
        this->WriteNumeric(RPL_YOURHOSTIS, InspIRCd::Format("Your host is %s, running version %s", ServerInstance->Config->ServerName.c_str(), INSPIRCD_BRANCH));
        this->WriteNumeric(RPL_SERVERCREATED, InspIRCd::TimeString(ServerInstance->startup_time, "This server was created %H:%M:%S %b %d %Y"));

        const TR1NS::array<std::string, 3>& modelist = ServerInstance->Modes->GetModeListFor004Numeric();
        this->WriteNumeric(RPL_SERVERVERSION, ServerInstance->Config->ServerName, INSPIRCD_BRANCH, modelist[0], modelist[1], modelist[2]);

        ServerInstance->ISupport.SendTo(this);

        /* Now registered */
        if (ServerInstance->Users->unregistered_count)
                ServerInstance->Users->unregistered_count--;

        /* Trigger MOTD and LUSERS output, give modules a chance too */
        ModResult MOD_RESULT;
        std::string command("LUSERS");
        std::vector<std::string> parameters;
        FIRST_MOD_RESULT(OnPreCommand, MOD_RESULT, (command, parameters, this, true, command));
        if (!MOD_RESULT)
                ServerInstance->Parser.CallHandler(command, parameters, this);

        MOD_RESULT = MOD_RES_PASSTHRU;
        command = "MOTD";
        FIRST_MOD_RESULT(OnPreCommand, MOD_RESULT, (command, parameters, this, true, command));
        if (!MOD_RESULT)
                ServerInstance->Parser.CallHandler(command, parameters, this);

        if (ServerInstance->Config->RawLog)
                WriteServ("PRIVMSG %s :*** Raw I/O logging is enabled on this server. All messages, passwords, and commands are being recorded.", nick.c_str());

        /*
         * We don't set REG_ALL until triggering OnUserConnect, so some module events don't spew out stuff
         * for a user that doesn't exist yet.
         */
        FOREACH_MOD(OnUserConnect, (this));

        this->registered = REG_ALL;

        FOREACH_MOD(OnPostConnect, (this));

        ServerInstance->SNO->WriteToSnoMask('c',"Client connecting on port %d (class %s): %s (%s) [%s]",
                this->GetServerPort(), this->MyClass->name.c_str(), GetFullRealHost().c_str(), this->GetIPString().c_str(), this->fullname.c_str());
        ServerInstance->Logs->Log("BANCACHE", LOG_DEBUG, "BanCache: Adding NEGATIVE hit for " + this->GetIPString());
        ServerInstance->BanCache.AddHit(this->GetIPString(), "", "");
        // reset the flood penalty (which could have been raised due to things like auto +x)
        CommandFloodPenalty = 0;
}

void User::InvalidateCache()
{
        /* Invalidate cache */
        cachedip.clear();
        cached_fullhost.clear();
        cached_hostip.clear();
        cached_makehost.clear();
        cached_fullrealhost.clear();
}

bool User::ChangeNick(const std::string& newnick, time_t newts)
{
        if (quitting)
        {
                ServerInstance->Logs->Log("USERS", LOG_DEFAULT, "ERROR: Attempted to change nick of a quitting user: " + this->nick);
                return false;
        }

        User* const InUse = ServerInstance->FindNickOnly(newnick);
        if (InUse == this)
        {
                // case change, don't need to check campers
                // and, if it's identical including case, we can leave right now
                // We also don't update the nick TS if it's a case change, either
                if (newnick == nick)
                        return true;
        }
        else
        {
                /*
                 * Uh oh.. if the nickname is in use, and it's not in use by the person using it (doh) --
                 * then we have a potential collide. Check whether someone else is camping on the nick
                 * (i.e. connect -> send NICK, don't send USER.) If they are camping, force-change the
                 * camper to their UID, and allow the incoming nick change.
                 *
                 * If the guy using the nick is already using it, tell the incoming nick change to gtfo,
                 * because the nick is already (rightfully) in use. -- w00t
                 */
                if (InUse)
                {
                        if (InUse->registered != REG_ALL)
                        {
                                /* force the camper to their UUID, and ask them to re-send a NICK. */
                                LocalUser* const localuser = static_cast<LocalUser*>(InUse);
                                localuser->OverruleNick();
                        }
                        else
                        {
                                /* No camping, tell the incoming user  to stop trying to change nick ;p */
                                this->WriteNumeric(ERR_NICKNAMEINUSE, newnick, "Nickname is already in use.");
                                return false;
                        }
                }

                age = newts ? newts : ServerInstance->Time();
        }

        if (this->registered == REG_ALL)
                this->WriteCommon("NICK %s", newnick.c_str());
        const std::string oldnick = nick;
        nick = newnick;

        InvalidateCache();
        ServerInstance->Users->clientlist.erase(oldnick);
        ServerInstance->Users->clientlist[newnick] = this;

        if (registered == REG_ALL)
                FOREACH_MOD(OnUserPostNick, (this,oldnick));

        return true;
}

void LocalUser::OverruleNick()
{
        this->WriteFrom(this, "NICK %s", this->uuid.c_str());
        this->WriteNumeric(ERR_NICKNAMEINUSE, this->nick, "Nickname overruled.");

        // Clear the bit before calling ChangeNick() to make it NOT run the OnUserPostNick() hook
        this->registered &= ~REG_NICK;
        this->ChangeNick(this->uuid);
}

int LocalUser::GetServerPort()
{
        return this->server_sa.port();
}

const std::string& User::GetIPString()
{
        if (cachedip.empty())
        {
                cachedip = client_sa.addr();
                /* IP addresses starting with a : on irc are a Bad Thing (tm) */
                if (cachedip[0] == ':')
                        cachedip.insert(cachedip.begin(),1,'0');
        }

        return cachedip;
}

const std::string& User::GetHost(bool uncloak) const
{
        return uncloak ? GetRealHost() : GetDisplayedHost();
}

const std::string& User::GetDisplayedHost() const
{
        return displayhost.empty() ? realhost : displayhost;
}

const std::string& User::GetRealHost() const
{
        return realhost;
}

irc::sockets::cidr_mask User::GetCIDRMask()
{
        unsigned char range = 0;
        switch (client_sa.family())
        {
                case AF_INET6:
                        range = ServerInstance->Config->c_ipv6_range;
                        break;
                case AF_INET:
                        range = ServerInstance->Config->c_ipv4_range;
                        break;
        }
        return irc::sockets::cidr_mask(client_sa, range);
}

bool User::SetClientIP(const std::string& address, bool recheck_eline)
{
        this->InvalidateCache();
        return irc::sockets::aptosa(address, 0, client_sa);
}

void User::SetClientIP(const irc::sockets::sockaddrs& sa, bool recheck_eline)
{
        this->InvalidateCache();
        memcpy(&client_sa, &sa, sizeof(irc::sockets::sockaddrs));
}

bool LocalUser::SetClientIP(const std::string& address, bool recheck_eline)
{
        irc::sockets::sockaddrs sa;
        if (!irc::sockets::aptosa(address, 0, sa))
                // Invalid
                return false;

        LocalUser::SetClientIP(sa, recheck_eline);
        return true;
}

void LocalUser::SetClientIP(const irc::sockets::sockaddrs& sa, bool recheck_eline)
{
        if (sa != client_sa)
        {
                User::SetClientIP(sa);
                if (recheck_eline)
                        this->exempt = (ServerInstance->XLines->MatchesLine("E", this) != NULL);

                FOREACH_MOD(OnSetUserIP, (this));
        }
}

static std::string wide_newline("\r\n");

void User::Write(const std::string& text)
{
}

void User::Write(const char *text, ...)
{
}

void LocalUser::Write(const std::string& text)
{
        if (!SocketEngine::BoundsCheckFd(&eh))
                return;

        // The maximum size of an IRC message minus the terminating CR+LF.
        const size_t maxmessage = ServerInstance->Config->Limits.MaxLine - 2;
        if (text.length() > maxmessage)
        {
                // This should happen rarely or never. Crop the string at MaxLine and try again.
                std::string try_again(text, 0, maxmessage);
                Write(try_again);
                return;
        }

        ServerInstance->Logs->Log("USEROUTPUT", LOG_RAWIO, "C[%s] O %s", uuid.c_str(), text.c_str());

        eh.AddWriteBuf(text);
        eh.AddWriteBuf(wide_newline);

        const size_t bytessent = text.length() + 2;
        ServerInstance->stats.Sent += bytessent;
        this->bytes_out += bytessent;
        this->cmds_out++;
}

/** Write()
 */
void LocalUser::Write(const char *text, ...)
{
        std::string textbuffer;
        VAFORMAT(textbuffer, text, text);
        this->Write(textbuffer);
}

void User::WriteServ(const std::string& text)
{
        this->Write(":%s %s",ServerInstance->Config->ServerName.c_str(),text.c_str());
}

/** WriteServ()
 *  Same as Write(), except `text' is prefixed with `:server.name '.
 */
void User::WriteServ(const char* text, ...)
{
        std::string textbuffer;
        VAFORMAT(textbuffer, text, text);
        this->WriteServ(textbuffer);
}

void User::WriteCommand(const char* command, const std::string& text)
{
        this->WriteServ(command + (this->registered & REG_NICK ? " " + this->nick : " *") + " " + text);
}

namespace
{
        std::string BuildNumeric(const std::string& source, User* targetuser, unsigned int num, const std::vector<std::string>& params)
        {
                const char* const target = (targetuser->registered & REG_NICK ? targetuser->nick.c_str() : "*");
                std::string raw = InspIRCd::Format(":%s %03u %s", source.c_str(), num, target);
                if (!params.empty())
                {
                        for (std::vector<std::string>::const_iterator i = params.begin(); i != params.end()-1; ++i)
                                raw.append(1, ' ').append(*i);
                        raw.append(" :").append(params.back());
                }
                return raw;
        }
}

void User::WriteNumeric(const Numeric::Numeric& numeric)
{
        ModResult MOD_RESULT;

        FIRST_MOD_RESULT(OnNumeric, MOD_RESULT, (this, numeric));

        if (MOD_RESULT == MOD_RES_DENY)
                return;

        const std::string& servername = (numeric.GetServer() ? numeric.GetServer()->GetName() : ServerInstance->Config->ServerName);
        this->Write(BuildNumeric(servername, this, numeric.GetNumeric(), numeric.GetParams()));
}

void User::WriteFrom(User *user, const std::string &text)
{
        const std::string message = ":" + user->GetFullHost() + " " + text;
        this->Write(message);
}


/* write text from an originating user to originating user */

void User::WriteFrom(User *user, const char* text, ...)
{
        std::string textbuffer;
        VAFORMAT(textbuffer, text, text);
        this->WriteFrom(user, textbuffer);
}

void User::WriteRemoteNotice(const std::string& text)
{
        ServerInstance->PI->SendUserNotice(this, text);
}

void LocalUser::WriteRemoteNotice(const std::string& text)
{
        WriteNotice(text);
}

namespace
{
        class WriteCommonRawHandler : public User::ForEachNeighborHandler
        {
                const std::string& msg;

                void Execute(LocalUser* user) CXX11_OVERRIDE
                {
                        user->Write(msg);
                }

         public:
                WriteCommonRawHandler(const std::string& message)
                        : msg(message)
                {
                }
        };
}

void User::WriteCommon(const char* text, ...)
{
        std::string textbuffer;
        VAFORMAT(textbuffer, text, text);
        textbuffer = ":" + this->GetFullHost() + " " + textbuffer;
        this->WriteCommonRaw(textbuffer, true);
}

void User::WriteCommonRaw(const std::string &line, bool include_self)
{
        WriteCommonRawHandler handler(line);
        ForEachNeighbor(handler, include_self);
}

void User::ForEachNeighbor(ForEachNeighborHandler& handler, bool include_self)
{
        // The basic logic for visiting the neighbors of a user is to iterate the channel list of the user
        // and visit all users on those channels. Because two users may share more than one common channel,
        // we must skip users that we have already visited.
        // To do this, we make use of a global counter and an integral 'already_sent' field in LocalUser.
        // The global counter is incremented every time we do something for each neighbor of a user. Then,
        // before visiting a member we examine user->already_sent. If it's equal to the current counter, we
        // skip the member. Otherwise, we set it to the current counter and visit the member.

        // Ask modules to build a list of exceptions.
        // Mods may also exclude entire channels by erasing them from include_chans.
        IncludeChanList include_chans(chans.begin(), chans.end());
        std::map<User*, bool> exceptions;
        exceptions[this] = include_self;
        FOREACH_MOD(OnBuildNeighborList, (this, include_chans, exceptions));

        // Get next id, guaranteed to differ from the already_sent field of all users
        const already_sent_t newid = ServerInstance->Users.NextAlreadySentId();

        // Handle exceptions first
        for (std::map<User*, bool>::const_iterator i = exceptions.begin(); i != exceptions.end(); ++i)
        {
                LocalUser* curr = IS_LOCAL(i->first);
                if (curr)
                {
                        // Mark as visited to ensure we won't visit again if there is a common channel
                        curr->already_sent = newid;
                        // Always treat quitting users as excluded
                        if ((i->second) && (!curr->quitting))
                                handler.Execute(curr);
                }
        }

        // Now consider the real neighbors
        for (IncludeChanList::const_iterator i = include_chans.begin(); i != include_chans.end(); ++i)
        {
                Channel* chan = (*i)->chan;
                const Channel::MemberMap& userlist = chan->GetUsers();
                for (Channel::MemberMap::const_iterator j = userlist.begin(); j != userlist.end(); ++j)
                {
                        LocalUser* curr = IS_LOCAL(j->first);
                        // User not yet visited?
                        if ((curr) && (curr->already_sent != newid))
                        {
                                // Mark as visited and execute function
                                curr->already_sent = newid;
                                handler.Execute(curr);
                        }
                }
        }
}

void User::WriteRemoteNumeric(const Numeric::Numeric& numeric)
{
        WriteNumeric(numeric);
}

/* return 0 or 1 depending if users u and u2 share one or more common channels
 * (used by QUIT, NICK etc which arent channel specific notices)
 *
 * The old algorithm in 1.0 for this was relatively inefficient, iterating over
 * the first users channels then the second users channels within the outer loop,
 * therefore it was a maximum of x*y iterations (upon returning 0 and checking
 * all possible iterations). However this new function instead checks against the
 * channel's userlist in the inner loop which is a std::map<User*,User*>
 * and saves us time as we already know what pointer value we are after.
 * Don't quote me on the maths as i am not a mathematician or computer scientist,
 * but i believe this algorithm is now x+(log y) maximum iterations instead.
 */
bool User::SharesChannelWith(User *other)
{
        /* Outer loop */
        for (User::ChanList::iterator i = this->chans.begin(); i != this->chans.end(); ++i)
        {
                /* Eliminate the inner loop (which used to be ~equal in size to the outer loop)
                 * by replacing it with a map::find which *should* be more efficient
                 */
                if ((*i)->chan->HasUser(other))
                        return true;
        }
        return false;
}

bool User::ChangeName(const std::string& gecos)
{
        if (!this->fullname.compare(gecos))
                return true;

        if (IS_LOCAL(this))
        {
                ModResult MOD_RESULT;
                FIRST_MOD_RESULT(OnChangeLocalUserGECOS, MOD_RESULT, (IS_LOCAL(this),gecos));
                if (MOD_RESULT == MOD_RES_DENY)
                        return false;
                FOREACH_MOD(OnChangeName, (this,gecos));
        }
        this->fullname.assign(gecos, 0, ServerInstance->Config->Limits.MaxGecos);

        return true;
}

bool User::ChangeDisplayedHost(const std::string& shost)
{
        if (GetDisplayedHost() == shost)
                return true;

        if (IS_LOCAL(this))
        {
                ModResult MOD_RESULT;
                FIRST_MOD_RESULT(OnChangeLocalUserHost, MOD_RESULT, (IS_LOCAL(this),shost));
                if (MOD_RESULT == MOD_RES_DENY)
                        return false;
        }

        FOREACH_MOD(OnChangeHost, (this,shost));

        if (realhost == shost)
                this->displayhost.clear();
        else
                this->displayhost.assign(shost, 0, ServerInstance->Config->Limits.MaxHost);

        this->InvalidateCache();

        if (IS_LOCAL(this))
                this->WriteNumeric(RPL_YOURDISPLAYEDHOST, this->GetDisplayedHost(), "is now your displayed host");

        return true;
}

void User::ChangeRealHost(const std::string& host, bool resetdisplay)
{
        // If the real host is the new host and we are not resetting the
        // display host then we have nothing to do.
        const bool changehost = (realhost != host);
        if (!changehost && !resetdisplay)
                return;
        
        // If the displayhost is not set and we are not resetting it then
        // we need to copy it to the displayhost field.
        if (displayhost.empty() && !resetdisplay)
                displayhost = realhost;

        // If the displayhost is the new host or we are resetting it then
        // we clear its contents to save memory.
        else if (displayhost == host || resetdisplay)
                displayhost.clear();

        // If we are just resetting the display host then we don't need to
        // do anything else.
        if (!changehost)
                return;

        realhost = host;
        this->InvalidateCache();
}

bool User::ChangeIdent(const std::string& newident)
{
        if (this->ident == newident)
                return true;

        FOREACH_MOD(OnChangeIdent, (this,newident));

        this->ident.assign(newident, 0, ServerInstance->Config->Limits.IdentMax);
        this->InvalidateCache();

        return true;
}

/*
 * Sets a user's connection class.
 * If the class name is provided, it will be used. Otherwise, the class will be guessed using host/ip/ident/etc.
 * NOTE: If the <ALLOW> or <DENY> tag specifies an ip, and this user resolves,
 * then their ip will be taken as 'priority' anyway, so for example,
 * <connect allow="127.0.0.1"> will match joe!bloggs@localhost
 */
void LocalUser::SetClass(const std::string &explicit_name)
{
        ConnectClass *found = NULL;

        ServerInstance->Logs->Log("CONNECTCLASS", LOG_DEBUG, "Setting connect class for UID %s", this->uuid.c_str());

        if (!explicit_name.empty())
        {
                for (ServerConfig::ClassVector::const_iterator i = ServerInstance->Config->Classes.begin(); i != ServerInstance->Config->Classes.end(); ++i)
                {
                        ConnectClass* c = *i;

                        if (explicit_name == c->name)
                        {
                                ServerInstance->Logs->Log("CONNECTCLASS", LOG_DEBUG, "Explicitly set to %s", explicit_name.c_str());
                                found = c;
                        }
                }
        }
        else
        {
                for (ServerConfig::ClassVector::const_iterator i = ServerInstance->Config->Classes.begin(); i != ServerInstance->Config->Classes.end(); ++i)
                {
                        ConnectClass* c = *i;
                        ServerInstance->Logs->Log("CONNECTCLASS", LOG_DEBUG, "Checking %s", c->GetName().c_str());

                        ModResult MOD_RESULT;
                        FIRST_MOD_RESULT(OnSetConnectClass, MOD_RESULT, (this,c));
                        if (MOD_RESULT == MOD_RES_DENY)
                                continue;
                        if (MOD_RESULT == MOD_RES_ALLOW)
                        {
                                ServerInstance->Logs->Log("CONNECTCLASS", LOG_DEBUG, "Class forced by module to %s", c->GetName().c_str());
                                found = c;
                                break;
                        }

                        if (c->type == CC_NAMED)
                                continue;

                        bool regdone = (registered != REG_NONE);
                        if (c->config->getBool("registered", regdone) != regdone)
                                continue;

                        /* check if host matches.. */
                        if (!InspIRCd::MatchCIDR(this->GetIPString(), c->GetHost(), NULL) &&
                            !InspIRCd::MatchCIDR(this->GetRealHost(), c->GetHost(), NULL))
                        {
                                ServerInstance->Logs->Log("CONNECTCLASS", LOG_DEBUG, "No host match (for %s)", c->GetHost().c_str());
                                continue;
                        }

                        /*
                         * deny change if change will take class over the limit check it HERE, not after we found a matching class,
                         * because we should attempt to find another class if this one doesn't match us. -- w00t
                         */
                        if (c->limit && (c->GetReferenceCount() >= c->limit))
                        {
                                ServerInstance->Logs->Log("CONNECTCLASS", LOG_DEBUG, "OOPS: Connect class limit (%lu) hit, denying", c->limit);
                                continue;
                        }

                        /* if it requires a port ... */
                        if (!c->ports.empty())
                        {
                                /* and our port doesn't match, fail. */
                                if (!c->ports.count(this->GetServerPort()))
                                {
                                        ServerInstance->Logs->Log("CONNECTCLASS", LOG_DEBUG, "Requires a different port, skipping");
                                        continue;
                                }
                        }

                        if (regdone && !c->config->getString("password").empty())
                        {
                                if (!ServerInstance->PassCompare(this, c->config->getString("password"), password, c->config->getString("hash")))
                                {
                                        ServerInstance->Logs->Log("CONNECTCLASS", LOG_DEBUG, "Bad password, skipping");
                                        continue;
                                }
                        }

                        /* we stop at the first class that meets ALL critera. */
                        found = c;
                        break;
                }
        }

        /*
         * Okay, assuming we found a class that matches.. switch us into that class, keeping refcounts up to date.
         */
        if (found)
        {
                MyClass = found;
        }
}

void User::PurgeEmptyChannels()
{
        // firstly decrement the count on each channel
        for (User::ChanList::iterator i = this->chans.begin(); i != this->chans.end(); )
        {
                Channel* c = (*i)->chan;
                ++i;
                c->DelUser(this);
        }

        this->UnOper();
}

const std::string& FakeUser::GetFullHost()
{
        if (!ServerInstance->Config->HideServer.empty())
                return ServerInstance->Config->HideServer;
        return server->GetName();
}

const std::string& FakeUser::GetFullRealHost()
{
        if (!ServerInstance->Config->HideServer.empty())
                return ServerInstance->Config->HideServer;
        return server->GetName();
}

ConnectClass::ConnectClass(ConfigTag* tag, char t, const std::string& mask)
        : config(tag), type(t), fakelag(true), name("unnamed"), registration_timeout(0), host(mask),
        pingtime(0), softsendqmax(0), hardsendqmax(0), recvqmax(0),
        penaltythreshold(0), commandrate(0), maxlocal(0), maxglobal(0), maxconnwarn(true), maxchans(ServerInstance->Config->MaxChans),
        limit(0), resolvehostnames(true)
{
}

ConnectClass::ConnectClass(ConfigTag* tag, char t, const std::string& mask, const ConnectClass& parent)
{
        Update(&parent);
        name = "unnamed";
        type = t;
        host = mask;

        // Connect classes can inherit from each other but this is problematic for modules which can't use
        // ConnectClass::Update so we build a hybrid tag containing all of the values set on this class as
        // well as the parent class.
        ConfigItems* items = NULL;
        config = ConfigTag::create(tag->tag, tag->src_name, tag->src_line, items);

        const ConfigItems& parentkeys = parent.config->getItems();
        for (ConfigItems::const_iterator piter = parentkeys.begin(); piter != parentkeys.end(); ++piter)
        {
                // The class name and parent name are not inherited
                if (piter->first == "name" || piter->first == "parent")
                        continue;

                // Store the item in the config tag. If this item also
                // exists in the child it will be overwritten.
                (*items)[piter->first] = piter->second;
        }

        const ConfigItems& childkeys = tag->getItems();
        for (ConfigItems::const_iterator citer = childkeys.begin(); citer != childkeys.end(); ++citer)
        {
                // This will overwrite the parent value if present.
                (*items)[citer->first] = citer->second;
        }
}

void ConnectClass::Update(const ConnectClass* src)
{
        config = src->config;
        type = src->type;
        fakelag = src->fakelag;
        name = src->name;
        registration_timeout = src->registration_timeout;
        host = src->host;
        pingtime = src->pingtime;
        softsendqmax = src->softsendqmax;
        hardsendqmax = src->hardsendqmax;
        recvqmax = src->recvqmax;
        penaltythreshold = src->penaltythreshold;
        commandrate = src->commandrate;
        maxlocal = src->maxlocal;
        maxglobal = src->maxglobal;
        maxconnwarn = src->maxconnwarn;
        maxchans = src->maxchans;
        limit = src->limit;
        resolvehostnames = src->resolvehostnames;
        ports = src->ports;
}