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-rw-r--r--src/modules/m_spanningtree/fjoin.cpp397
1 files changed, 242 insertions, 155 deletions
diff --git a/src/modules/m_spanningtree/fjoin.cpp b/src/modules/m_spanningtree/fjoin.cpp
index 4ec6e1dbb..c292373b3 100644
--- a/src/modules/m_spanningtree/fjoin.cpp
+++ b/src/modules/m_spanningtree/fjoin.cpp
@@ -25,11 +25,26 @@
#include "treeserver.h"
#include "treesocket.h"
+/** FJOIN builder for rebuilding incoming FJOINs and splitting them up into multiple messages if necessary
+ */
+class FwdFJoinBuilder : public CommandFJoin::Builder
+{
+ TreeServer* const sourceserver;
+
+ public:
+ FwdFJoinBuilder(Channel* chan, TreeServer* server)
+ : CommandFJoin::Builder(chan, server)
+ , sourceserver(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(const std::vector<std::string>& params, User *srcuser)
+CmdResult CommandFJoin::Handle(User* srcuser, std::vector<std::string>& params)
{
- SpanningTreeUtilities* Utils = ((ModuleSpanningTree*)(Module*)creator)->Utils;
- /* 1.1 FJOIN works as follows:
+ /* 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
@@ -54,204 +69,276 @@ CmdResult CommandFJoin::Handle(const std::vector<std::string>& params, User *src
* 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 ecounters 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.
+ * One incoming FJOIN may result in more than one FJOIN being generated
+ * and forwarded mainly due to compatibility reasons with non-InspIRCd
+ * servers that don't handle more than 512 char long lines.
+ *
+ * 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.
+ *
*/
- irc::modestacker modestack(true); /* Modes to apply from the users in the user list */
- User* 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 */
- irc::tokenstream users((params.size() > 3) ? params[params.size() - 1] : ""); /* users from the user list */
- bool apply_other_sides_modes = true; /* True if we are accepting the other side's modes */
- Channel* chan = ServerInstance->FindChan(channel); /* The channel we're sending joins to */
- bool created = !chan; /* True if the channel doesnt exist here yet */
- std::string item; /* One item in the list of nicks */
-
- TreeServer* src_server = Utils->FindServer(srcuser->server);
- TreeSocket* src_socket = src_server->GetRoute()->GetSocket();
+ time_t TS = ServerCommand::ExtractTS(params[1]);
- if (!TS)
- {
- ServerInstance->Logs->Log("m_spanningtree",DEFAULT,"*** BUG? *** TS of 0 sent to FJOIN. Are some services authors smoking craq, or is it 1970 again?. Dropped.");
- ServerInstance->SNO->WriteToSnoMask('d', "WARNING: The server %s is sending FJOIN with a TS of zero. Total craq. Command was dropped.", srcuser->server.c_str());
- return CMD_INVALID;
- }
+ const std::string& channel = params[0];
+ Channel* chan = ServerInstance->FindChan(channel);
+ bool apply_other_sides_modes = true;
+ TreeServer* const sourceserver = TreeServer::Get(srcuser);
- if (created)
+ if (!chan)
{
chan = new Channel(channel, TS);
- ServerInstance->SNO->WriteToSnoMask('d', "Creation FJOIN received for %s, timestamp: %lu", chan->name.c_str(), (unsigned long)TS);
}
else
{
time_t ourTS = chan->age;
-
if (TS != ourTS)
+ {
ServerInstance->SNO->WriteToSnoMask('d', "Merge FJOIN received for %s, ourTS: %lu, TS: %lu, difference: %ld",
chan->name.c_str(), (unsigned long)ourTS, (unsigned long)TS, (long)(ourTS - TS));
- /* If our TS is less than theirs, we dont accept their modes */
- if (ourTS < TS)
- {
- ServerInstance->SNO->WriteToSnoMask('d', "NOT Applying modes from other side");
- apply_other_sides_modes = false;
- }
- else if (ourTS > TS)
- {
- /* Our TS greater than theirs, clear all our modes from the channel, accept theirs. */
- ServerInstance->SNO->WriteToSnoMask('d', "Removing our modes, accepting remote");
- parameterlist param_list;
- if (Utils->AnnounceTSChange)
- chan->WriteChannelWithServ(ServerInstance->Config->ServerName, "NOTICE %s :TS for %s changed from %lu to %lu", chan->name.c_str(), channel.c_str(), (unsigned long) ourTS, (unsigned long) TS);
- // while the name is equal in case-insensitive compare, it might differ in case; use the remote version
- chan->name = channel;
- chan->age = TS;
- chan->ClearInvites();
- param_list.push_back(channel);
- this->RemoveStatus(ServerInstance->FakeClient, param_list);
-
- // 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->FindChan(channel) == NULL)
+ /* If our TS is less than theirs, we dont accept their modes */
+ if (ourTS < TS)
{
- chan = new Channel(channel, 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->Log(MODNAME, LOG_DEBUG, "Server %s recreated channel %s with higher TS, resyncing", sourceserver->GetName().c_str(), chan->name.c_str());
+ 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->FindChan(channel) == NULL)
+ {
+ chan = new Channel(channel, TS);
+ }
}
}
- // The silent case here is ourTS == TS, we don't need to remove modes here, just to merge them later on.
}
- /* First up, apply their modes if they won the TS war */
+ // Apply their channel modes if we have to
+ Modes::ChangeList modechangelist;
if (apply_other_sides_modes)
{
- // Need to use a modestacker here due to maxmodes
- irc::modestacker stack(true);
- std::vector<std::string>::const_iterator paramit = params.begin() + 3;
- const std::vector<std::string>::const_iterator lastparamit = ((params.size() > 3) ? (params.end() - 1) : params.end());
- for (std::string::const_iterator i = params[2].begin(); i != params[2].end(); ++i)
- {
- ModeHandler* mh = ServerInstance->Modes->FindMode(*i, MODETYPE_CHANNEL);
- if (!mh)
- continue;
+ ServerInstance->Modes.ModeParamsToChangeList(srcuser, MODETYPE_CHANNEL, params, modechangelist, 2, params.size() - 1);
+ ServerInstance->Modes->Process(srcuser, chan, NULL, modechangelist, ModeParser::MODE_LOCALONLY | ModeParser::MODE_MERGE);
+ // Reuse for prefix modes
+ modechangelist.clear();
+ }
- std::string modeparam;
- if ((paramit != lastparamit) && (mh->GetNumParams(true)))
- {
- modeparam = *paramit;
- ++paramit;
- }
+ // 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);
- stack.Push(*i, modeparam);
- }
+ // Process every member in the message
+ irc::tokenstream users(params.back());
+ std::string item;
+ Modes::ChangeList* modechangelistptr = (apply_other_sides_modes ? &modechangelist : NULL);
+ while (users.GetToken(item))
+ {
+ ProcessModeUUIDPair(item, sourceserver, chan, modechangelistptr, fwdfjoin);
+ }
- std::vector<std::string> modelist;
+ fwdfjoin.finalize();
+ fwdfjoin.Forward(sourceserver->GetRoute());
- // Mode parser needs to know what channel to act on.
- modelist.push_back(params[0]);
+ // 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, NULL, modechangelist, ModeParser::MODE_LOCALONLY);
- while (stack.GetStackedLine(modelist))
- {
- ServerInstance->Modes->Process(modelist, srcuser, true);
- modelist.erase(modelist.begin() + 1, modelist.end());
- }
+ return CMD_SUCCESS;
+}
+
+void CommandFJoin::ProcessModeUUIDPair(const std::string& item, TreeServer* sourceserver, Channel* chan, Modes::ChangeList* modechangelist, FwdFJoinBuilder& fwdfjoin)
+{
+ std::string::size_type comma = item.find(',');
- ServerInstance->Modes->Process(modelist, srcuser, true);
+ // 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);
+ User* who = ServerInstance->FindUUID(uuid);
+ if (!who)
+ {
+ // Probably KILLed, ignore
+ return;
}
- /* Now, process every 'modes,nick' pair */
- while (users.GetToken(item))
+ 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)
{
- const char* usr = item.c_str();
- if (usr && *usr)
+ 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)
{
- const char* unparsedmodes = usr;
- std::string modes;
+ 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);
+ }
+ }
- /* Iterate through all modes for this user and check they are valid. */
- while ((*unparsedmodes) && (*unparsedmodes != ','))
- {
- ModeHandler *mh = ServerInstance->Modes->FindMode(*unparsedmodes, MODETYPE_CHANNEL);
- if (!mh)
- {
- ServerInstance->Logs->Log("m_spanningtree", SPARSE, "Unrecognised mode %c, dropping link", *unparsedmodes);
- return CMD_INVALID;
- }
+ Membership* memb = chan->ForceJoin(who, NULL, 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;
+ }
- modes += *unparsedmodes;
- usr++;
- unparsedmodes++;
- }
+ // 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;
- /* Advance past the comma, to the nick */
- usr++;
+ // Add member to fwdfjoin with prefix modes
+ fwdfjoin.add(memb, item.begin(), modeendit);
+}
- /* Check the user actually exists */
- who = ServerInstance->FindUUID(usr);
- if (who)
- {
- /* Check that the user's 'direction' is correct */
- TreeServer* route_back_again = Utils->BestRouteTo(who->server);
- if ((!route_back_again) || (route_back_again->GetSocket() != src_socket))
- continue;
+void CommandFJoin::RemoveStatus(Channel* c)
+{
+ Modes::ChangeList changelist;
- /* Add any modes this user had to the mode stack */
- for (std::string::iterator x = modes.begin(); x != modes.end(); ++x)
- modestack.Push(*x, who->nick);
+ const ModeParser::ModeHandlerMap& mhs = ServerInstance->Modes->GetModes(MODETYPE_CHANNEL);
+ for (ModeParser::ModeHandlerMap::const_iterator i = mhs.begin(); i != mhs.end(); ++i)
+ {
+ ModeHandler* mh = i->second;
- Channel::JoinUser(who, channel.c_str(), true, "", src_server->bursting, TS);
- }
- else
- {
- ServerInstance->Logs->Log("m_spanningtree",SPARSE, "Ignored nonexistent user %s in fjoin to %s (probably quit?)", usr, channel.c_str());
- continue;
- }
- }
+ // Add the removal of this mode to the changelist. This handles all kinds of modes, including prefix modes.
+ mh->RemoveMode(c, changelist);
}
- /* Flush mode stacker if we lost the FJOIN or had equal TS */
- if (apply_other_sides_modes)
- {
- parameterlist stackresult;
- stackresult.push_back(channel);
+ ServerInstance->Modes->Process(ServerInstance->FakeClient, c, NULL, changelist, ModeParser::MODE_LOCALONLY);
+}
- while (modestack.GetStackedLine(stackresult))
- {
- ServerInstance->SendMode(stackresult, srcuser);
- stackresult.erase(stackresult.begin() + 1, stackresult.end());
- }
- }
- return CMD_SUCCESS;
+void CommandFJoin::LowerTS(Channel* chan, time_t TS, const std::string& newname)
+{
+ if (Utils->AnnounceTSChange)
+ chan->WriteNotice(InspIRCd::Format("TS for %s changed from %lu to %lu", newname.c_str(), (unsigned long) chan->age, (unsigned long) 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();
}
-void CommandFJoin::RemoveStatus(User* srcuser, parameterlist &params)
+CommandFJoin::Builder::Builder(Channel* chan, TreeServer* source)
+ : CmdBuilder(source->GetID(), "FJOIN")
{
- if (params.size() < 1)
- return;
+ push(chan->name).push_int(chan->age).push_raw(" +");
+ pos = str().size();
+ push_raw(chan->ChanModes(true)).push_raw(" :");
+}
- Channel* c = ServerInstance->FindChan(params[0]);
+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(' ');
+}
- if (c)
- {
- irc::modestacker stack(false);
- parameterlist stackresult;
- stackresult.push_back(c->name);
+bool CommandFJoin::Builder::has_room(std::string::size_type nummodes) const
+{
+ return ((str().size() + nummodes + UIDGenerator::UUID_LENGTH + 2 + membid_max_digits + 1) <= maxline);
+}
- for (char modeletter = 'A'; modeletter <= 'z'; ++modeletter)
- {
- ModeHandler* mh = ServerInstance->Modes->FindMode(modeletter, MODETYPE_CHANNEL);
-
- /* Passing a pointer to a modestacker here causes the mode to be put onto the mode stack,
- * rather than applied immediately. Module unloads require this to be done immediately,
- * for this function we require tidyness instead. Fixes bug #493
- */
- if (mh)
- mh->RemoveMode(c, &stack);
- }
+void CommandFJoin::Builder::clear()
+{
+ content.erase(pos);
+ push_raw(" :");
+}
- while (stack.GetStackedLine(stackresult))
- {
- ServerInstance->SendMode(stackresult, srcuser);
- stackresult.erase(stackresult.begin() + 1, stackresult.end());
- }
- }
+const std::string& CommandFJoin::Builder::finalize()
+{
+ if (*content.rbegin() == ' ')
+ content.erase(content.size()-1);
+ return str();
}
+void FwdFJoinBuilder::add(Membership* memb, std::string::const_iterator mbegin, std::string::const_iterator mend)
+{
+ // Pseudoserver compatibility:
+ // Some pseudoservers do not handle lines longer than 512 so we split long FJOINs into multiple messages.
+ // The forwarded FJOIN can end up being longer than the original one if we have more modes set and won, for example.
+
+ // Check if the member fits into the current message. If not, send it and prepare a new one.
+ if (!has_room(std::distance(mbegin, mend)))
+ {
+ finalize();
+ Forward(sourceserver);
+ clear();
+ }
+ // Add the member and their modes exactly as they sent them
+ CommandFJoin::Builder::add(memb, mbegin, mend);
+}
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