summaryrefslogtreecommitdiff
path: root/src/modules/m_messageflood.cpp
blob: 9ff17924d1c38bbb154c4a959fa151824894a221 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
/*
 * InspIRCd -- Internet Relay Chat Daemon
 *
 *   Copyright (C) 2009 Daniel De Graaf <danieldg@inspircd.org>
 *   Copyright (C) 2008 Pippijn van Steenhoven <pip88nl@gmail.com>
 *   Copyright (C) 2007 Robin Burchell <robin+git@viroteck.net>
 *   Copyright (C) 2007 John Brooks <john.brooks@dereferenced.net>
 *   Copyright (C) 2007 Dennis Friis <peavey@inspircd.org>
 *   Copyright (C) 2006 Craig Edwards <craigedwards@brainbox.cc>
 *   Copyright (C) 2006 Oliver Lupton <oliverlupton@gmail.com>
 *
 * 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"

/* $ModDesc: Provides channel mode +f (message flood protection) */

/** Holds flood settings and state for mode +f
 */
class floodsettings
{
 public:
	bool ban;
	unsigned int secs;
	unsigned int lines;
	time_t reset;
	std::map<User*, unsigned int> counters;

	floodsettings(bool a, int b, int c) : ban(a), secs(b), lines(c)
	{
		reset = ServerInstance->Time() + secs;
	}

	bool addmessage(User* who)
	{
		if (ServerInstance->Time() > reset)
		{
			counters.clear();
			reset = ServerInstance->Time() + secs;
		}

		return (++counters[who] >= this->lines);
	}

	void clear(User* who)
	{
		std::map<User*, unsigned int>::iterator iter = counters.find(who);
		if (iter != counters.end())
		{
			counters.erase(iter);
		}
	}
};

/** Handles channel mode +f
 */
class MsgFlood : public ModeHandler
{
 public:
	SimpleExtItem<floodsettings> ext;
	MsgFlood(Module* Creator) : ModeHandler(Creator, "flood", 'f', PARAM_SETONLY, MODETYPE_CHANNEL),
		ext("messageflood", Creator) { }

	ModeAction OnModeChange(User* source, User* dest, Channel* channel, std::string &parameter, bool adding)
	{
		if (adding)
		{
			std::string::size_type colon = parameter.find(':');
			if ((colon == std::string::npos) || (parameter.find('-') != std::string::npos))
			{
				source->WriteNumeric(608, "%s %s :Invalid flood parameter",source->nick.c_str(),channel->name.c_str());
				return MODEACTION_DENY;
			}

			/* Set up the flood parameters for this channel */
			bool ban = (parameter[0] == '*');
			unsigned int nlines = ConvToInt(parameter.substr(ban ? 1 : 0, ban ? colon-1 : colon));
			unsigned int nsecs = ConvToInt(parameter.substr(colon+1));

			if ((nlines<2) || (nsecs<1))
			{
				source->WriteNumeric(608, "%s %s :Invalid flood parameter",source->nick.c_str(),channel->name.c_str());
				return MODEACTION_DENY;
			}

			floodsettings* f = ext.get(channel);
			if ((f) && (nlines == f->lines) && (nsecs == f->secs) && (ban == f->ban))
				// mode params match
				return MODEACTION_DENY;

			ext.set(channel, new floodsettings(ban, nsecs, nlines));
			parameter = std::string(ban ? "*" : "") + ConvToStr(nlines) + ":" + ConvToStr(nsecs);
			channel->SetModeParam('f', parameter);
			return MODEACTION_ALLOW;
		}
		else
		{
			if (!channel->IsModeSet('f'))
				return MODEACTION_DENY;

			ext.unset(channel);
			channel->SetModeParam('f', "");
			return MODEACTION_ALLOW;
		}
	}
};

class ModuleMsgFlood : public Module
{
	MsgFlood mf;

 public:

	ModuleMsgFlood()
		: mf(this)
	{
	}

	void init()
	{
		ServerInstance->Modules->AddService(mf);
		ServerInstance->Modules->AddService(mf.ext);
		Implementation eventlist[] = { I_OnUserPreNotice, I_OnUserPreMessage };
		ServerInstance->Modules->Attach(eventlist, this, sizeof(eventlist)/sizeof(Implementation));
	}

	ModResult ProcessMessages(User* user,Channel* dest, const std::string &text)
	{
		if ((!IS_LOCAL(user)) || !dest->IsModeSet('f'))
			return MOD_RES_PASSTHRU;

		if (ServerInstance->OnCheckExemption(user,dest,"flood") == MOD_RES_ALLOW)
			return MOD_RES_PASSTHRU;

		floodsettings *f = mf.ext.get(dest);
		if (f)
		{
			if (f->addmessage(user))
			{
				/* Youre outttta here! */
				f->clear(user);
				if (f->ban)
				{
					std::vector<std::string> parameters;
					parameters.push_back(dest->name);
					parameters.push_back("+b");
					parameters.push_back(user->MakeWildHost());
					ServerInstance->SendGlobalMode(parameters, ServerInstance->FakeClient);
				}

				char kickmessage[MAXBUF];
				snprintf(kickmessage, MAXBUF, "Channel flood triggered (limit is %u lines in %u secs)", f->lines, f->secs);

				dest->KickUser(ServerInstance->FakeClient, user, kickmessage);

				return MOD_RES_DENY;
			}
		}

		return MOD_RES_PASSTHRU;
	}

	ModResult OnUserPreMessage(User *user, void *dest, int target_type, std::string &text, char status, CUList &exempt_list)
	{
		if (target_type == TYPE_CHANNEL)
			return ProcessMessages(user,(Channel*)dest,text);

		return MOD_RES_PASSTHRU;
	}

	ModResult OnUserPreNotice(User *user, void *dest, int target_type, std::string &text, char status, CUList &exempt_list)
	{
		if (target_type == TYPE_CHANNEL)
			return ProcessMessages(user,(Channel*)dest,text);

		return MOD_RES_PASSTHRU;
	}

	void Prioritize()
	{
		// we want to be after all modules that might deny the message (e.g. m_muteban, m_noctcp, m_blockcolor, etc.)
		ServerInstance->Modules->SetPriority(this, I_OnUserPreMessage, PRIORITY_LAST);
		ServerInstance->Modules->SetPriority(this, I_OnUserPreNotice, PRIORITY_LAST);
	}

	Version GetVersion()
	{
		return Version("Provides channel mode +f (message flood protection)", VF_VENDOR);
	}
};

MODULE_INIT(ModuleMsgFlood)