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authorGravatar Sadie Powell2024-07-17 00:06:50 +0100
committerGravatar Sadie Powell2024-07-17 00:06:50 +0100
commit889d521e05f2e922683d48c74eb00290e7a2f548 (patch)
treeb4c56bd4cdf0881601c7e4d6ff571e491af10bf4 /src/modules/m_spanningtree/fjoin.cpp
parentUse std::endian from C++20 in the sha1 module. (diff)
Shuffle the modules about a bit.
Diffstat (limited to 'src/modules/m_spanningtree/fjoin.cpp')
-rw-r--r--src/modules/m_spanningtree/fjoin.cpp332
1 files changed, 0 insertions, 332 deletions
diff --git a/src/modules/m_spanningtree/fjoin.cpp b/src/modules/m_spanningtree/fjoin.cpp
deleted file mode 100644
index d2329c76b..000000000
--- a/src/modules/m_spanningtree/fjoin.cpp
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@@ -1,332 +0,0 @@
-/*
- * InspIRCd -- Internet Relay Chat Daemon
- *
- * Copyright (C) 2018-2023 Sadie Powell <sadie@witchery.services>
- * Copyright (C) 2012-2016 Attila Molnar <attilamolnar@hush.com>
- * Copyright (C) 2012 Robby <robby@chatbelgie.be>
- * Copyright (C) 2009-2010 Daniel De Graaf <danieldg@inspircd.org>
- * Copyright (C) 2008, 2012 Robin Burchell <robin+git@viroteck.net>
- * Copyright (C) 2008 Craig Edwards <brain@inspircd.org>
- *
- * 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 "timeutils.h"
-
-#include "commands.h"
-#include "treeserver.h"
-#include "treesocket.h"
-
-/** FJOIN builder for rebuilding incoming FJOINs and splitting them up into multiple messages if necessary
- */
-class FwdFJoinBuilder final
- : public CommandFJoin::Builder
-{
-public:
- FwdFJoinBuilder(Channel* chan, TreeServer* server)
- : CommandFJoin::Builder(chan, server)
- {
- }
-
- void add(Membership* memb, std::string::const_iterator mbegin, std::string::const_iterator mend);
-};
-
-/** FJOIN, almost identical to TS6 SJOIN, except for nicklist handling. */
-CmdResult CommandFJoin::Handle(User* srcuser, Params& 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 privileges
- * 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 of its
- * modes from the channel, before introducing new users into the channel
- * which are listed in the FJOIN command's parameters. 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 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. :-)
- *
- * Outside of netbursts, the winning side also resyncs the losing side if it
- * detects that the other side recreated the channel.
- *
- * Syntax:
- * :<sid> FJOIN <chan> <TS> <modes> :[<member> [<member> ...]]
- * The last parameter is a list consisting of zero or more channel members
- * (permanent channels may have zero users). Each entry on the list is in the
- * following format:
- * [[<modes>,]<uuid>[:<membid>]
- * <modes> is a concatenation of the mode letters the user has on the channel
- * (e.g.: "ov" if the user is opped and voiced). The order of the mode letters
- * are not important but if a server encounters an unknown mode letter, it will
- * drop the link to avoid desync.
- *
- * InspIRCd 2.0 and older required a comma before the uuid even if the user
- * had no prefix modes on the channel, InspIRCd 3.0 and later does not require
- * a comma in this case anymore.
- *
- * <membid> is a positive integer representing the id of the membership.
- * If not present (in FJOINs coming from pre-1205 servers), 0 is assumed.
- *
- * Forwarding:
- * FJOIN messages are forwarded with the new TS and modes. Prefix modes of
- * members on the losing side are not forwarded.
- * This is required to only have one server on each side of the network who
- * decides the fate of a channel during a network merge. Otherwise, if the
- * clock of a server is slightly off it may make a different decision than
- * the rest of the network and desync.
- * The prefix modes are always forwarded as-is, or not at all.
- *
- * Forwarding examples:
- * Existing channel #chan with TS 1000, modes +n.
- * Incoming: :220 FJOIN #chan 1000 +t :o,220AAAAAB:0
- * Forwarded: :220 FJOIN #chan 1000 +nt :o,220AAAAAB:0
- * Merge modes and forward the result. Forward their prefix modes as well.
- *
- * Existing channel #chan with TS 1000, modes +nt.
- * Incoming: :220 FJOIN #CHAN 2000 +i :ov,220AAAAAB:0 o,220AAAAAC:20
- * Forwarded: :220 FJOIN #chan 1000 +nt :,220AAAAAB:0 ,220AAAAAC:20
- * Drop their modes, forward our modes and TS, use our channel name
- * capitalization. Don't forward prefix modes.
- *
- */
-
- time_t TS = ServerCommand::ExtractTS(params[1]);
-
- const std::string& channel = params[0];
- auto* chan = ServerInstance->Channels.Find(channel);
- bool apply_other_sides_modes = true;
- TreeServer* const sourceserver = TreeServer::Get(srcuser);
-
- if (!chan)
- {
- if (!ServerInstance->Channels.IsPrefix(channel[0]))
- throw ProtocolException("Malformed channel name in FJOIN: " + channel);
-
- chan = new Channel(channel, TS);
- }
- else
- {
- time_t ourTS = chan->age;
- if (TS != ourTS)
- {
- ServerInstance->Logs.Debug(MODNAME, "Merge FJOIN received for {}, ourTS: {}, TS: {}, difference: {}",
- chan->name, ourTS, TS, ourTS - TS);
- /* If our TS is less than theirs, we dont accept their modes */
- if (ourTS < TS)
- {
- // If the source server isn't bursting then this FJOIN is the result of them recreating the channel with a higher TS.
- // This happens if the last user on the channel hops and before the PART propagates a user on another server joins. Fix it by doing a resync.
- // Servers behind us won't react this way because the forwarded FJOIN will have the correct TS.
- if (!sourceserver->IsBursting())
- {
- ServerInstance->Logs.Debug(MODNAME, "Server {} recreated channel {} with higher TS, resyncing", sourceserver->GetName(), chan->name);
- sourceserver->GetSocket()->SyncChannel(chan);
- }
- apply_other_sides_modes = false;
- }
- else if (ourTS > TS)
- {
- // Our TS is greater than theirs, remove all modes, extensions, etc. from the channel
- LowerTS(chan, TS, channel);
-
- // XXX: If the channel does not exist in the chan hash at this point, create it so the remote modes can be applied on it.
- // This happens to 0-user permanent channels on the losing side, because those are removed (from the chan hash, then
- // deleted later) as soon as the permchan mode is removed from them.
- if (!ServerInstance->Channels.Find(channel))
- {
- chan = new Channel(channel, TS);
- }
- }
- }
- }
-
- // Apply their channel modes if we have to
- Modes::ChangeList modechangelist;
- if (apply_other_sides_modes)
- {
- ServerInstance->Modes.ModeParamsToChangeList(srcuser, MODETYPE_CHANNEL, params, modechangelist, 2, params.size() - 1);
- ServerInstance->Modes.Process(srcuser, chan, nullptr, modechangelist, ModeParser::MODE_LOCALONLY | ModeParser::MODE_MERGE);
- // Reuse for prefix modes
- modechangelist.clear();
- }
-
- // Build a new FJOIN for forwarding. Put the correct TS in it and the current modes of the channel
- // after applying theirs. If they lost, the prefix modes from their message are not forwarded.
- FwdFJoinBuilder fwdfjoin(chan, sourceserver);
-
- // Process every member in the message
- irc::spacesepstream users(params.back());
- std::string item;
- Modes::ChangeList* modechangelistptr = (apply_other_sides_modes ? &modechangelist : nullptr);
- while (users.GetToken(item))
- {
- ProcessModeUUIDPair(item, sourceserver, chan, modechangelistptr, fwdfjoin);
- }
-
- fwdfjoin.finalize();
- fwdfjoin.Forward(sourceserver->GetRoute());
-
- // Set prefix modes on their users if we lost the FJOIN or had equal TS
- if (apply_other_sides_modes)
- ServerInstance->Modes.Process(srcuser, chan, nullptr, modechangelist, ModeParser::MODE_LOCALONLY);
-
- return CmdResult::SUCCESS;
-}
-
-void CommandFJoin::ProcessModeUUIDPair(const std::string& item, TreeServer* sourceserver, Channel* chan, Modes::ChangeList* modechangelist, FwdFJoinBuilder& fwdfjoin)
-{
- std::string::size_type comma = item.find(',');
-
- // Comma not required anymore if the user has no modes
- const std::string::size_type ubegin = (comma == std::string::npos ? 0 : comma+1);
- std::string uuid(item, ubegin, UIDGenerator::UUID_LENGTH);
- auto* who = ServerInstance->Users.FindUUID(uuid);
- if (!who)
- {
- // Probably KILLed, ignore
- return;
- }
-
- TreeSocket* src_socket = sourceserver->GetSocket();
- /* Check that the user's 'direction' is correct */
- TreeServer* route_back_again = TreeServer::Get(who);
- if (route_back_again->GetSocket() != src_socket)
- {
- return;
- }
-
- std::string::const_iterator modeendit = item.begin(); // End of the "ov" mode string
- /* Check if the user received at least one mode */
- if ((modechangelist) && (comma != std::string::npos))
- {
- modeendit += comma;
- /* Iterate through the modes and see if they are valid here, if so, apply */
- for (std::string::const_iterator i = item.begin(); i != modeendit; ++i)
- {
- ModeHandler* mh = ServerInstance->Modes.FindMode(*i, MODETYPE_CHANNEL);
- if (!mh)
- throw ProtocolException("Unrecognised mode '" + std::string(1, *i) + "'");
-
- /* Add any modes this user had to the mode stack */
- modechangelist->push_add(mh, who->nick);
- }
- }
-
- Membership* memb = chan->ForceJoin(who, nullptr, sourceserver->IsBursting());
- if (!memb)
- {
- // User was already on the channel, forward because of the modes they potentially got
- memb = chan->GetUser(who);
- if (memb)
- fwdfjoin.add(memb, item.begin(), modeendit);
- return;
- }
-
- // Assign the id to the new Membership
- Membership::Id membid = 0;
- const std::string::size_type colon = item.rfind(':');
- if (colon != std::string::npos)
- membid = Membership::IdFromString(item.substr(colon+1));
- memb->id = membid;
-
- // Add member to fwdfjoin with prefix modes
- fwdfjoin.add(memb, item.begin(), modeendit);
-}
-
-void CommandFJoin::RemoveStatus(Channel* c)
-{
- Modes::ChangeList changelist;
-
- for (const auto& [_, mh] : ServerInstance->Modes.GetModes(MODETYPE_CHANNEL))
- {
- // Add the removal of this mode to the changelist. This handles all kinds of modes, including prefix modes.
- mh->RemoveMode(c, changelist);
- }
-
- ServerInstance->Modes.Process(ServerInstance->FakeClient, c, nullptr, changelist, ModeParser::MODE_LOCALONLY);
-}
-
-void CommandFJoin::LowerTS(Channel* chan, time_t TS, const std::string& newname)
-{
- if (Utils->AnnounceTSChange)
- {
- // WriteRemoteNotice is not used here because the message only needs to go to the local server.
- chan->WriteNotice(fmt::format("Creation time of {} changed from {} to {}", newname,
- Time::ToString(chan->age), Time::ToString(TS)));
- }
-
- // While the name is equal in case-insensitive compare, it might differ in case; use the remote version
- chan->name = newname;
- chan->age = TS;
-
- // Clear all modes
- CommandFJoin::RemoveStatus(chan);
-
- // Unset all extensions
- chan->FreeAllExtItems();
-
- // Clear the topic
- chan->SetTopic(ServerInstance->FakeClient, std::string(), 0);
- chan->setby.clear();
-}
-
-CommandFJoin::Builder::Builder(Channel* chan, TreeServer* source)
- : CmdBuilder(source, "FJOIN")
-{
- push(chan->name).push_int(chan->age).push_raw(" +");
- pos = str().size();
- push_raw(chan->ChanModes(true)).push_raw(" :");
-}
-
-void CommandFJoin::Builder::add(Membership* memb, std::string::const_iterator mbegin, std::string::const_iterator mend)
-{
- push_raw(mbegin, mend).push_raw(',').push_raw(memb->user->uuid);
- push_raw(':').push_raw_int(memb->id);
- push_raw(' ');
-}
-
-void CommandFJoin::Builder::clear()
-{
- content.erase(pos);
- push_raw(" :");
-}
-
-const std::string& CommandFJoin::Builder::finalize()
-{
- if (content.back() == ' ')
- content.pop_back();
- return str();
-}
-
-void FwdFJoinBuilder::add(Membership* memb, std::string::const_iterator mbegin, std::string::const_iterator mend)
-{
- // Add the member and their modes exactly as they sent them
- CommandFJoin::Builder::add(memb, mbegin, mend);
-}