diff options
| author | 2024-07-17 00:06:50 +0100 | |
|---|---|---|
| committer | 2024-07-17 00:06:50 +0100 | |
| commit | 889d521e05f2e922683d48c74eb00290e7a2f548 (patch) | |
| tree | b4c56bd4cdf0881601c7e4d6ff571e491af10bf4 /src/modules/m_spanningtree/fjoin.cpp | |
| parent | Use 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.cpp | 332 |
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 +++ /dev/null @@ -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); -} |
