diff options
Diffstat (limited to 'src/modules/m_repeat.cpp')
| -rw-r--r-- | src/modules/m_repeat.cpp | 419 |
1 files changed, 419 insertions, 0 deletions
diff --git a/src/modules/m_repeat.cpp b/src/modules/m_repeat.cpp new file mode 100644 index 000000000..609fd9d60 --- /dev/null +++ b/src/modules/m_repeat.cpp @@ -0,0 +1,419 @@ +/* + * InspIRCd -- Internet Relay Chat Daemon + * + * Copyright (C) 2013 Daniel Vassdal <shutter@canternet.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 "modules/exemption.h" + +class ChannelSettings +{ + public: + enum RepeatAction + { + ACT_KICK, + ACT_BLOCK, + ACT_BAN + }; + + RepeatAction Action; + unsigned int Backlog; + unsigned int Lines; + unsigned int Diff; + unsigned long Seconds; + + void serialize(std::string& out) const + { + if (Action == ACT_BAN) + out.push_back('*'); + else if (Action == ACT_BLOCK) + out.push_back('~'); + + out.append(ConvToStr(Lines)).push_back(':'); + out.append(ConvToStr(Seconds)); + if (Diff) + { + out.push_back(':'); + out.append(ConvToStr(Diff)); + if (Backlog) + { + out.push_back(':'); + out.append(ConvToStr(Backlog)); + } + } + } +}; + +class RepeatMode : public ParamMode<RepeatMode, SimpleExtItem<ChannelSettings> > +{ + private: + struct RepeatItem + { + time_t ts; + std::string line; + RepeatItem(time_t TS, const std::string& Line) : ts(TS), line(Line) { } + }; + + typedef std::deque<RepeatItem> RepeatItemList; + + struct MemberInfo + { + RepeatItemList ItemList; + unsigned int Counter; + MemberInfo() : Counter(0) {} + }; + + struct ModuleSettings + { + unsigned int MaxLines; + unsigned int MaxSecs; + unsigned int MaxBacklog; + unsigned int MaxDiff; + unsigned int MaxMessageSize; + ModuleSettings() : MaxLines(0), MaxSecs(0), MaxBacklog(0), MaxDiff() { } + }; + + std::vector<unsigned int> mx[2]; + ModuleSettings ms; + + bool CompareLines(const std::string& message, const std::string& historyline, unsigned int trigger) + { + if (message == historyline) + return true; + else if (trigger) + return (Levenshtein(message, historyline) <= trigger); + + return false; + } + + unsigned int Levenshtein(const std::string& s1, const std::string& s2) + { + unsigned int l1 = s1.size(); + unsigned int l2 = s2.size(); + + for (unsigned int i = 0; i < l2; i++) + mx[0][i] = i; + for (unsigned int i = 0; i < l1; i++) + { + mx[1][0] = i + 1; + for (unsigned int j = 0; j < l2; j++) + mx[1][j + 1] = std::min(std::min(mx[1][j] + 1, mx[0][j + 1] + 1), mx[0][j] + ((s1[i] == s2[j]) ? 0 : 1)); + + mx[0].swap(mx[1]); + } + return mx[0][l2]; + } + + public: + SimpleExtItem<MemberInfo> MemberInfoExt; + + RepeatMode(Module* Creator) + : ParamMode<RepeatMode, SimpleExtItem<ChannelSettings> >(Creator, "repeat", 'E') + , MemberInfoExt("repeat_memb", ExtensionItem::EXT_MEMBERSHIP, Creator) + { + } + + void OnUnset(User* source, Channel* chan) CXX11_OVERRIDE + { + // Unset the per-membership extension when the mode is removed + const Channel::MemberMap& users = chan->GetUsers(); + for (Channel::MemberMap::const_iterator i = users.begin(); i != users.end(); ++i) + MemberInfoExt.unset(i->second); + } + + ModeAction OnSet(User* source, Channel* channel, std::string& parameter) CXX11_OVERRIDE + { + ChannelSettings settings; + if (!ParseSettings(source, parameter, settings)) + { + source->WriteNumeric(Numerics::InvalidModeParameter(channel, this, parameter, + "Invalid repeat syntax. Syntax is: [~|*]<lines>:<sec>[:<difference>][:<backlog>]")); + return MODEACTION_DENY; + } + + if ((settings.Backlog > 0) && (settings.Lines > settings.Backlog)) + { + source->WriteNumeric(Numerics::InvalidModeParameter(channel, this, parameter, + "Invalid repeat syntax. You can't set lines higher than backlog.")); + return MODEACTION_DENY; + } + + LocalUser* localsource = IS_LOCAL(source); + if ((localsource) && (!ValidateSettings(localsource, channel, parameter, settings))) + return MODEACTION_DENY; + + ext.set(channel, settings); + + return MODEACTION_ALLOW; + } + + bool MatchLine(Membership* memb, ChannelSettings* rs, std::string message) + { + // If the message is larger than whatever size it's set to, + // let's pretend it isn't. If the first 512 (def. setting) match, it's probably spam. + if (message.size() > ms.MaxMessageSize) + message.erase(ms.MaxMessageSize); + + MemberInfo* rp = MemberInfoExt.get(memb); + if (!rp) + { + rp = new MemberInfo; + MemberInfoExt.set(memb, rp); + } + + unsigned int matches = 0; + if (!rs->Backlog) + matches = rp->Counter; + + RepeatItemList& items = rp->ItemList; + const unsigned int trigger = (message.size() * rs->Diff / 100); + const time_t now = ServerInstance->Time(); + + std::transform(message.begin(), message.end(), message.begin(), ::tolower); + + for (std::deque<RepeatItem>::iterator it = items.begin(); it != items.end(); ++it) + { + if (it->ts < now) + { + items.erase(it, items.end()); + matches = 0; + break; + } + + if (CompareLines(message, it->line, trigger)) + { + if (++matches >= rs->Lines) + { + if (rs->Action != ChannelSettings::ACT_BLOCK) + rp->Counter = 0; + return true; + } + } + else if ((ms.MaxBacklog == 0) || (rs->Backlog == 0)) + { + matches = 0; + items.clear(); + break; + } + } + + unsigned int max_items = (rs->Backlog ? rs->Backlog : 1); + if (items.size() >= max_items) + items.pop_back(); + + items.push_front(RepeatItem(now + rs->Seconds, message)); + rp->Counter = matches; + return false; + } + + void Resize(size_t size) + { + size_t newsize = size+1; + if (newsize <= mx[0].size()) + return; + ms.MaxMessageSize = size; + mx[0].resize(newsize); + mx[1].resize(newsize); + } + + void ReadConfig() + { + ConfigTag* conf = ServerInstance->Config->ConfValue("repeat"); + ms.MaxLines = conf->getUInt("maxlines", 20); + ms.MaxBacklog = conf->getUInt("maxbacklog", 20); + ms.MaxSecs = conf->getDuration("maxtime", conf->getDuration("maxsecs", 0)); + + ms.MaxDiff = conf->getUInt("maxdistance", 50); + if (ms.MaxDiff > 100) + ms.MaxDiff = 100; + + unsigned int newsize = conf->getUInt("size", 512); + if (newsize > ServerInstance->Config->Limits.MaxLine) + newsize = ServerInstance->Config->Limits.MaxLine; + Resize(newsize); + } + + std::string GetModuleSettings() const + { + return ConvToStr(ms.MaxLines) + ":" + ConvToStr(ms.MaxSecs) + ":" + ConvToStr(ms.MaxDiff) + ":" + ConvToStr(ms.MaxBacklog); + } + + void SerializeParam(Channel* chan, const ChannelSettings* chset, std::string& out) + { + chset->serialize(out); + } + + private: + bool ParseSettings(User* source, std::string& parameter, ChannelSettings& settings) + { + irc::sepstream stream(parameter, ':'); + std::string item; + if (!stream.GetToken(item)) + // Required parameter missing + return false; + + if ((item[0] == '*') || (item[0] == '~')) + { + settings.Action = ((item[0] == '*') ? ChannelSettings::ACT_BAN : ChannelSettings::ACT_BLOCK); + item.erase(item.begin()); + } + else + settings.Action = ChannelSettings::ACT_KICK; + + if ((settings.Lines = ConvToNum<unsigned int>(item)) == 0) + return false; + + if (!InspIRCd::Duration(item, settings.Seconds)) + return false; + + if ((!stream.GetToken(item)) || (settings.Seconds == 0)) + // Required parameter missing + return false; + + // The diff and backlog parameters are optional + settings.Diff = settings.Backlog = 0; + if (stream.GetToken(item)) + { + // There is a diff parameter, see if it's valid (> 0) + if ((settings.Diff = ConvToNum<unsigned int>(item)) == 0) + return false; + + if (stream.GetToken(item)) + { + // There is a backlog parameter, see if it's valid + if ((settings.Backlog = ConvToNum<unsigned int>(item)) == 0) + return false; + + // If there are still tokens, then it's invalid because we allow only 4 + if (stream.GetToken(item)) + return false; + } + } + + return true; + } + + bool ValidateSettings(LocalUser* source, Channel* channel, const std::string& parameter, const ChannelSettings& settings) + { + if (ms.MaxLines && settings.Lines > ms.MaxLines) + { + source->WriteNumeric(Numerics::InvalidModeParameter(channel, this, parameter, InspIRCd::Format( + "Invalid repeat parameter. The line number you specified is too great. Maximum allowed is %u.", ms.MaxLines))); + return false; + } + + if (ms.MaxSecs && settings.Seconds > ms.MaxSecs) + { + source->WriteNumeric(Numerics::InvalidModeParameter(channel, this, parameter, InspIRCd::Format( + "Invalid repeat parameter. The seconds you specified are too great. Maximum allowed is %u.", ms.MaxSecs))); + return false; + } + + if (settings.Diff && settings.Diff > ms.MaxDiff) + { + if (ms.MaxDiff == 0) + source->WriteNumeric(Numerics::InvalidModeParameter(channel, this, parameter, + "Invalid repeat parameter. The server administrator has disabled matching on edit distance.")); + else + source->WriteNumeric(Numerics::InvalidModeParameter(channel, this, parameter, InspIRCd::Format( + "Invalid repeat parameter. The distance you specified is too great. Maximum allowed is %u.", ms.MaxDiff))); + return false; + } + + if (settings.Backlog && settings.Backlog > ms.MaxBacklog) + { + if (ms.MaxBacklog == 0) + source->WriteNumeric(Numerics::InvalidModeParameter(channel, this, parameter, + "Invalid repeat parameter. The server administrator has disabled backlog matching.")); + else + source->WriteNumeric(Numerics::InvalidModeParameter(channel, this, parameter, InspIRCd::Format( + "Invalid repeat paramter. The backlog you specified is too great. Maximum allowed is %u.", ms.MaxBacklog))); + return false; + } + + return true; + } +}; + +class RepeatModule : public Module +{ + CheckExemption::EventProvider exemptionprov; + RepeatMode rm; + + public: + RepeatModule() + : exemptionprov(this) + , rm(this) + { + } + + void ReadConfig(ConfigStatus& status) CXX11_OVERRIDE + { + rm.ReadConfig(); + } + + ModResult OnUserPreMessage(User* user, const MessageTarget& target, MessageDetails& details) CXX11_OVERRIDE + { + if (target.type != MessageTarget::TYPE_CHANNEL || !IS_LOCAL(user)) + return MOD_RES_PASSTHRU; + + Channel* chan = target.Get<Channel>(); + ChannelSettings* settings = rm.ext.get(chan); + if (!settings) + return MOD_RES_PASSTHRU; + + Membership* memb = chan->GetUser(user); + if (!memb) + return MOD_RES_PASSTHRU; + + ModResult res = CheckExemption::Call(exemptionprov, user, chan, "repeat"); + if (res == MOD_RES_ALLOW) + return MOD_RES_PASSTHRU; + + if (rm.MatchLine(memb, settings, details.text)) + { + if (settings->Action == ChannelSettings::ACT_BLOCK) + { + user->WriteNotice("*** This line is too similar to one of your last lines."); + return MOD_RES_DENY; + } + + if (settings->Action == ChannelSettings::ACT_BAN) + { + Modes::ChangeList changelist; + changelist.push_add(ServerInstance->Modes->FindMode('b', MODETYPE_CHANNEL), "*!*@" + user->GetDisplayedHost()); + ServerInstance->Modes->Process(ServerInstance->FakeClient, chan, NULL, changelist); + } + + memb->chan->KickUser(ServerInstance->FakeClient, user, "Repeat flood"); + return MOD_RES_DENY; + } + return MOD_RES_PASSTHRU; + } + + void Prioritize() CXX11_OVERRIDE + { + ServerInstance->Modules->SetPriority(this, I_OnUserPreMessage, PRIORITY_LAST); + } + + Version GetVersion() CXX11_OVERRIDE + { + return Version("Provides channel mode +E, blocking of similar messages", VF_COMMON|VF_VENDOR, rm.GetModuleSettings()); + } +}; + +MODULE_INIT(RepeatModule) |