Add m_nickflood: Provides usermode +F nickchanges:seconds - allows nickchanges:seconds on a per-channel basis before denying further changes by any user on that channel. Requested in bug #325 by Potter. Works with <options:exemptchanops>, too.

git-svn-id: http://svn.inspircd.org/repository/trunk/inspircd@7665 e03df62e-2008-0410-955e-edbf42e46eb7

1 files changed, 284 insertions, 0 deletions

diff --git a/src/modules/m_nickflood.cpp b/src/modules/m_nickflood.cpp
new file mode 100644
index 000000000..4799bd4ef
--- /dev/null
+++ b/src/modules/m_nickflood.cpp
@@ -0,0 +1,284 @@
+/*       +------------------------------------+
+ *       | Inspire Internet Relay Chat Daemon |
+ *       +------------------------------------+
+ *
+ *  InspIRCd: (C) 2002-2007 InspIRCd Development Team
+ * See: http://www.inspircd.org/wiki/index.php/Credits
+ *
+ * This program is free but copyrighted software; see
+ *            the file COPYING for details.
+ *
+ * ---------------------------------------------------
+ */
+
+#include "inspircd.h"
+#include "users.h"
+#include "channels.h"
+#include "modules.h"
+
+/* $ModDesc: Provides channel mode +F (nick flood protection) */
+
+/** Holds settings and state associated with channel mode +F
+ */
+class nickfloodsettings : public classbase
+{
+ public:
+
+	int secs;
+	int nicks;
+	time_t reset;
+	time_t unlocktime;
+	int counter;
+	bool locked;
+	InspIRCd* ServerInstance;
+
+	nickfloodsettings() : secs(0), nicks(0) {};
+
+	nickfloodsettings(int b, int c) : secs(b), nicks(c)
+	{
+		reset = time(NULL) + secs;
+		counter = 0;
+		locked = false;
+	};
+
+	void addnick()
+	{
+		counter++;
+		if (time(NULL) > reset)
+		{
+			counter = 0;
+			reset = time(NULL) + secs;
+		}
+	}
+
+	bool shouldlock()
+	{
+		return (counter >= this->nicks);
+	}
+
+	void clear()
+	{
+		counter = 0;
+	}
+
+	bool islocked()
+	{
+		if (locked)
+		{
+			if (time(NULL) > unlocktime)
+			{
+				locked = false;
+				return false;
+			}
+			else
+			{
+				return true;
+			}
+		}
+		return false;
+	}
+
+	void lock()
+	{
+		locked = true;
+		unlocktime = time(NULL) + 60;
+	}
+
+};
+
+/** Handles channel mode +j
+ */
+class NickFlood : public ModeHandler
+{
+ public:
+	NickFlood(InspIRCd* Instance) : ModeHandler(Instance, 'F', 1, 0, false, MODETYPE_CHANNEL, false) { }
+
+	ModePair ModeSet(userrec* source, userrec* dest, chanrec* channel, const std::string &parameter)
+	{
+		nickfloodsettings* x;
+		if (channel->GetExt("nickflood",x))
+			return std::make_pair(true, ConvToStr(x->nicks)+":"+ConvToStr(x->secs));
+		else
+			return std::make_pair(false, parameter);
+	} 
+
+	bool CheckTimeStamp(time_t theirs, time_t ours, const std::string &their_param, const std::string &our_param, chanrec* channel)
+	{
+		/* When TS is equal, the alphabetically later one wins */
+		return (their_param < our_param);
+	}
+
+	ModeAction OnModeChange(userrec* source, userrec* dest, chanrec* channel, std::string &parameter, bool adding)
+	{
+		nickfloodsettings* dummy;
+
+		if (adding)
+		{
+			char ndata[MAXBUF];
+			char* data = ndata;
+			strlcpy(ndata,parameter.c_str(),MAXBUF);
+			char* nicks = data;
+			char* secs = NULL;
+			while (*data)
+			{
+				if (*data == ':')
+				{
+					*data = 0;
+					data++;
+					secs = data;
+					break;
+				}
+				else data++;
+			}
+			if (secs)
+
+			{
+				/* Set up the flood parameters for this channel */
+				int nnicks = atoi(nicks);
+				int nsecs = atoi(secs);
+				if ((nnicks<1) || (nsecs<1))
+				{
+					source->WriteServ("608 %s %s :Invalid flood parameter",source->nick,channel->name);
+					parameter.clear();
+					return MODEACTION_DENY;
+				}
+				else
+				{
+					if (!channel->GetExt("nickflood", dummy))
+					{
+						parameter = ConvToStr(nnicks) + ":" +ConvToStr(nsecs);
+						nickfloodsettings *f = new nickfloodsettings(nsecs,nnicks);
+						channel->Extend("nickflood", f);
+						channel->SetMode('F', true);
+						channel->SetModeParam('F', parameter.c_str(), true);
+						return MODEACTION_ALLOW;
+					}
+					else
+					{
+						std::string cur_param = channel->GetModeParameter('F');
+						parameter = ConvToStr(nnicks) + ":" +ConvToStr(nsecs);
+						if (cur_param == parameter)
+						{
+							// mode params match
+							return MODEACTION_DENY;
+						}
+						else
+						{
+							// new mode param, replace old with new
+							if ((nsecs > 0) && (nnicks > 0))
+							{
+								nickfloodsettings* f;
+								channel->GetExt("nickflood", f);
+								delete f;
+								f = new nickfloodsettings(nsecs, nnicks);
+								channel->Shrink("nickflood");
+								channel->Extend("nickflood", f);
+								channel->SetModeParam('F', cur_param.c_str(), false);
+								channel->SetModeParam('F', parameter.c_str(), true);
+								return MODEACTION_ALLOW;
+							}
+							else
+							{
+								return MODEACTION_DENY;
+							}
+						}
+					}
+				}
+			}
+			else
+			{
+				source->WriteServ("608 %s %s :Invalid flood parameter",source->nick,channel->name);
+				return MODEACTION_DENY;
+			}
+		}
+		else
+		{
+			if (channel->GetExt("nickflood", dummy))
+			{
+				nickfloodsettings *f;
+				channel->GetExt("nickflood", f);
+				DELETE(f);
+				channel->Shrink("nickflood");
+				channel->SetMode('F', false);
+				return MODEACTION_ALLOW;
+			}
+		}
+		return MODEACTION_DENY;
+	}
+};
+
+class ModuleNickFlood : public Module
+{
+	NickFlood* jf;
+	
+ public:
+ 
+	ModuleNickFlood(InspIRCd* Me)
+		: Module(Me)
+	{
+		
+		jf = new NickFlood(ServerInstance);
+		if (!ServerInstance->AddMode(jf, 'F'))
+			throw ModuleException("Could not add new modes!");
+	}
+
+	virtual int OnUserPreNick(userrec* user, const std::string &newnick)
+	{
+		for (UCListIter i = user->chans.begin(); i != user->chans.end(); i++)
+		{
+			chanrec *channel = i->first;
+
+			nickfloodsettings *f;
+			if (channel->GetExt("nickflood", f))
+			{
+				if (CHANOPS_EXEMPT(ServerInstance, 'F') && channel->GetStatus(user) == STATUS_OP)
+					continue;
+
+				if (f->islocked())
+				{
+					user->WriteServ("447 %s :%s has been locked for nickchanges for 60 seconds because there have been more than %d nick changes in %d seconds", user->nick, channel->name, f->nicks, f->secs);
+					return 1;
+				}
+
+				f->addnick();
+				if (f->shouldlock())
+				{
+					f->clear();
+					f->lock();
+					channel->WriteChannelWithServ((char*)ServerInstance->Config->ServerName, "NOTICE %s :No nick changes are allowed for 60 seconds because there have been more than %d nick changes in %d seconds.", channel->name, f->nicks, f->secs);
+					return 1;
+				}
+			}
+		}
+
+		return 0;
+	}
+	
+	void OnChannelDelete(chanrec* chan)
+	{
+		nickfloodsettings *f;
+		if (chan->GetExt("nickflood",f))
+		{
+			DELETE(f);
+			chan->Shrink("nickflood");
+		}
+	}
+
+	void Implements(char* List)
+	{
+		List[I_OnChannelDelete] = List[I_OnUserPreNick] = 1;
+	}
+
+	virtual ~ModuleNickFlood()
+	{
+		ServerInstance->Modes->DelMode(jf);
+		DELETE(jf);
+	}
+	
+	virtual Version GetVersion()
+	{
+		return Version(1, 1, 0, 0, VF_COMMON | VF_VENDOR, API_VERSION);
+	}
+};
+
+MODULE_INIT(ModuleNickFlood)