path: root/src/modules/m_dccallow.cpp

 /* m_dccallow - Jamie Penman-Smithson <jamie@silverdream.org> - September 2006 */

using namespace std;

#include <stdio.h>
#include <vector>
#include <string.h>
#include "users.h"
#include "channels.h"
#include "modules.h"
#include "inspircd.h"

/* $ModDesc: Povides support for the /DCCALLOW command */

static ConfigReader *Conf;

class BannedFileList
{
 public:
    std::string filemask;
    std::string action;
};

class DCCAllow
{
 public:
    std::string nickname;
    std::string hostmask;
    time_t set_on;
    long length;

    DCCAllow() { }

    DCCAllow(std::string nick, std::string hm, time_t so, long ln) : nickname(nick), hostmask(hm), set_on(so), length(ln) { }
};

typedef std::vector<userrec *> userlist;
userlist ul;
typedef std::vector<DCCAllow> dccallowlist;
dccallowlist* dl;
typedef std::vector<BannedFileList> bannedfilelist;
bannedfilelist bfl;

class cmd_dccallow : public command_t
{
 public:
    cmd_dccallow(InspIRCd* Me) : command_t(Me, "DCCALLOW", 0, 0)
    {
	this->source = "m_dccallow.so";
	syntax = "{[+|-]<nick> <time>}";
    }

    CmdResult Handle(const char **parameters, int pcnt, userrec *user)
    {
	/* syntax: DCCALLOW [+|-]<nick> (<time>) */
	
	if (!pcnt)
	{
	    // display current DCCALLOW list
	    DisplayDCCAllowList(user);

	    return CMD_SUCCESS;
	}
	else if (pcnt > 0)
	{
	    char action = *parameters[0];
	
	    // if they didn't specify an action, this is probably a command
	    if (action != '+' && action != '-')
	    {
		if (!strcasecmp(parameters[0], "LIST"))
		{
		    // list current DCCALLOW list
		    DisplayDCCAllowList(user);
		    return CMD_SUCCESS;
		} 
		else if (!strcasecmp(parameters[0], "HELP"))
		{
		    // display help
		    DisplayHelp(user);
		    return CMD_SUCCESS;
		}
	    }
		
	    std::string nick = parameters[0] + 1;
	    userrec *target = ServerInstance->FindNick(nick);

	    if (target)
	    {
		ServerInstance->Log(DEBUG, "m_dccallow.so: got target %s and action %c", target->nick, action);
			    
		if (action == '-')
		{
		    user->GetExt("dccallow_list", dl);
		    // check if it contains any entries
		    if (dl)
		    {
			if (dl->size())
			{
			    for (dccallowlist::iterator i = dl->begin(); i != dl->end(); ++i)
			    {
				// search through list
				if (i->nickname == target->nick)
				{
				    dl->erase(i);
				    user->WriteServ("995 %s %s :Removed %s from your DCCALLOW list", user->nick, user->nick, target->nick);
				    break;
				}
			    }
			}
		    }
		    else
		    {
			DELETE(dl);
			user->Shrink("dccallow_list");
			
			// remove from userlist
			for (userlist::iterator j = ul.begin(); j != ul.end(); ++j)
			{
			    userrec* u = (userrec*)(*j);
			    if (u->nick == user->nick)
			    {
				ul.erase(j);
				break;
			    }
			}
		    }
		}
		else if (action == '+')
		{
		    // fetch current DCCALLOW list
		    user->GetExt("dccallow_list", dl);
		    // they don't have one, create it
		    if (!dl)
		    {
			dl = new dccallowlist;
			user->Extend(std::string("dccallow_list"), dl);
			// add this user to the userlist
			ul.push_back(user);
		    }
		    for (dccallowlist::const_iterator k = dl->begin(); k != dl->end(); ++k)
		    {
			if (k->nickname == target->nick)
			{
			    user->WriteServ("996 %s %s :%s is already on your DCCALLOW list", user->nick, user->nick, target->nick);
			    return CMD_SUCCESS;
			}
		    }
		
		    std::string mask = std::string(target->nick)+"!"+std::string(target->ident)+"@"+std::string(target->dhost);
		    const char* default_length = Conf->ReadValue("dccallow", "length", 0).c_str();

		    long length;
		    if (pcnt == 1 || ServerInstance->Duration(parameters[1]) < 1)
		    {
			length = ServerInstance->Duration(default_length);
		    } 
		    else if (parameters[1] == 0)
		    {
			length = 0;
		    }
		    else
		    {
			length = ServerInstance->Duration(parameters[1]);
		    }

		    if (!ServerInstance->IsValidMask(mask.c_str()))
		    {
			return CMD_FAILURE;
		    }
		    
		    dl->push_back(DCCAllow(target->nick, mask, ServerInstance->Time(), length));

		    if (length > 0)
		    {
			user->WriteServ("993 %s %s :Added %s to DCCALLOW list for %d seconds", user->nick, user->nick, target->nick, length);
		    }
		    else
		    {
			user->WriteServ("994 %s %s :Added %s to DCCALLOW list for this session", user->nick, user->nick, target->nick);
		    }
		    
		    return CMD_SUCCESS;
		}
	    }
	    else
	    {
		// nick doesn't exist
		user->WriteServ("401 %s %s :No such nick/channel", user->nick, nick.c_str());
		return CMD_FAILURE;
	    }
	}
    return CMD_SUCCESS;
    }

    void DisplayHelp(userrec* user)
    {
	user->WriteServ("998 %s :DCCALLOW [<+|->nick [time]] [list] [help]", user->nick);
	user->WriteServ("998 %s :You may allow DCCs from specific users by specifying a", user->nick);
	user->WriteServ("998 %s :DCC allow for the user you want to receive DCCs from.", user->nick);
	user->WriteServ("998 %s :For example, to allow the user Brain to send you inspircd.exe", user->nick);
	user->WriteServ("998 %s :you would type:", user->nick);
	user->WriteServ("998 %s :/DCCALLOW +Brain", user->nick);
	user->WriteServ("998 %s :Brain would then be able to send you files. They would have to", user->nick);
	user->WriteServ("998 %s :resend the file again if the server gave them an error message", user->nick);
	user->WriteServ("998 %s :before you added them to your DCCALLOW list.", user->nick);
	user->WriteServ("998 %s :DCCALLOW entries will be temporary by default, if you want to add", user->nick);
	user->WriteServ("998 %s :them to your DCCALLOW list until you leave IRC, type:", user->nick);
	user->WriteServ("998 %s :/DCCALLOW +Brain 0", user->nick);
	user->WriteServ("998 %s :To remove the user from your DCCALLOW list, type:", user->nick);
	user->WriteServ("998 %s :/DCCALLOW -Brain", user->nick);
	user->WriteServ("998 %s :To see the users in your DCCALLOW list, type:", user->nick);
	user->WriteServ("998 %s :/DCCALLOW LIST", user->nick);
	user->WriteServ("998 %s :NOTE: If the user leaves IRC or changes their nickname", user->nick);
	user->WriteServ("998 %s :      they will be removed from your DCCALLOW list.", user->nick);
	user->WriteServ("998 %s :      your DCCALLOW list will be deleted when you leave IRC.", user->nick);
	user->WriteServ("999 %s :End of DCCALLOW HELP", user->nick);
    }

    void DisplayDCCAllowList(userrec* user)
    {
	 // display current DCCALLOW list
	user->WriteServ("990 %s :Users on your DCCALLOW list:", user->nick);
	user->GetExt("dccallow_list", dl);
	
	if (dl)
	{
	    for (dccallowlist::const_iterator c = dl->begin(); c != dl->end(); ++c)
	    {
		user->WriteServ("991 %s %s :%s (%s)", user->nick, user->nick, c->nickname.c_str(), c->hostmask.c_str());
	    }
	}
	
	user->WriteServ("992 %s :End of DCCALLOW list", user->nick);
    }			

};
	
class ModuleDCCAllow : public Module
{
    cmd_dccallow* mycommand;

 public:
    ModuleDCCAllow(InspIRCd* Me)
	: Module::Module(Me)
    {
	Conf = new ConfigReader(ServerInstance);
	mycommand = new cmd_dccallow(ServerInstance);
	ServerInstance->AddCommand(mycommand);
	ReadFileConf();
    }

    void Implements(char* List)
    {
	List[I_OnUserPreMessage] = List[I_OnUserPreNotice] = List[I_OnUserQuit] = List[I_OnUserPreNick] = List[I_OnRehash] = 1;
    }

    virtual void OnRehash(const std::string &parameter)
    {
		delete Conf;
	Conf = new ConfigReader(ServerInstance);
    }

    virtual void OnUserQuit(userrec* user, const std::string &reason)
    {
	dccallowlist* dl;

	// remove their DCCALLOW list if they have one
	user->GetExt("dccallow_list", dl);
	if (dl)
	{
	    DELETE(dl);
	    user->Shrink("dccallow_list");
	    RemoveFromUserlist(user);
	}
	
	// remove them from any DCCALLOW lists
	// they are currently on
	RemoveNick(user);
    }


    virtual int OnUserPreNick(userrec* user, const std::string &newnick)
    {
	RemoveNick(user);
	return 0;
    }
    
    virtual int OnUserPreMessage(userrec* user, void* dest, int target_type, std::string &text, char status)
    {
	return OnUserPreNotice(user, dest, target_type, text, status);
    }

    virtual int OnUserPreNotice(userrec* user, void* dest, int target_type, std::string &text, char status)
    {
	Expire();

	if (target_type == TYPE_USER)
	{
	    userrec* u = (userrec*)dest;
	    
	    if ((text.length()) && (text[0] == '\1'))
	    {
		// :jamie!jamie@test-D4457903BA652E0F.silverdream.org PRIVMSG eimaj :DCC SEND m_dnsbl.cpp 3232235786 52650 9676
		// :jamie!jamie@test-D4457903BA652E0F.silverdream.org PRIVMSG eimaj :VERSION
			
		if (strncmp(text.c_str(), "\1DCC ", 5) == 0)
		{
		    u->GetExt("dccallow_list", dl);

		    if (dl)
		    {
			if (dl->size())
			{
			    for (dccallowlist::const_iterator iter = dl->begin(); iter != dl->end(); ++iter)
			    {
				if (ServerInstance->MatchText(user->GetFullHost(), iter->hostmask))
				{
				    return 0;
				}
			    }
			}
		    }

		    // tokenize
		    stringstream ss(text);
		    std::string buf;
		    vector<string> tokens;

		    while (ss >> buf)
			tokens.push_back(buf);

		    irc::string type = tokens[1].c_str();
		    ServerInstance->Log(DEBUG, "m_dccallow.so: got DCC type %s", type.c_str());

		    const char* blockchat = Conf->ReadValue("dccallow", "blockchat", 0).c_str();
		    ServerInstance->Log(DEBUG, "m_dccallow.so: got blockchat: %s", blockchat);

		    if (type == "SEND")
		    {
			const char* defaultaction = Conf->ReadValue("dccallow", "action", 0).c_str();
			std::string filename = tokens[2];
			
			if (strcmp(defaultaction, "allow") == 0) 
			{
			    return 0;
			}
			
			for (unsigned int i = 0; i < bfl.size(); i++)
			{
			    if (ServerInstance->MatchText(filename, bfl[i].filemask))
			    {
				if (strcmp(bfl[i].action.c_str(), "allow") == 0)
				{
				    return 0;
				}
			    }
			    else
			    {
				if (strcmp(defaultaction, "allow") == 0)
				{
				    return 0;
				}
			    }
			    user->WriteServ("NOTICE %s :The user %s is not accepting DCC SENDs from you. Your file %s was not sent.", user->nick, u->nick, filename.c_str());
			    u->WriteServ("NOTICE %s :%s (%s@%s) attempted to send you a file named %s, which was blocked.", u->nick, user->nick, user->ident, user->dhost, filename.c_str());
			    u->WriteServ("NOTICE %s :If you trust %s and were expecting this, you can type /DCCALLOW HELP for information on the DCCALLOW system.", u->nick, user->nick);
			}
		    }
		    else if ((type == "CHAT") && (strcmp(blockchat, "yes") == 0))
		    {
			user->WriteServ("NOTICE %s :The user %s is not accepting DCC CHAT requests from you.", user->nick, u->nick);
			u->WriteServ("NOTICE %s :%s (%s@%s) attempted to initiate a DCC CHAT session, which was blocked.", u->nick, user->nick, user->ident, user->dhost);
			u->WriteServ("NOTICE %s :If you trust %s and were expecting this, you can type /DCCALLOW HELP for information on the DCCALLOW system.", u->nick, user->nick);
		    }
		    return 1;    
		}
	    }
	}
	return 0;
    }

    void Expire()
    {
	for (userlist::iterator iter = ul.begin(); iter != ul.end(); ++iter)
	{
	    userrec* u = (userrec*)(*iter);
	    u->GetExt("dccallow_list", dl);

	    if (dl)
	    {
		if (dl->size())
		{
		    dccallowlist::iterator iter = dl->begin();
		    while (iter != dl->end())
		    {
			if ((iter->set_on + iter->length) <= ServerInstance->Time())
			{
			    u->WriteServ("997 %s %s :DCCALLOW entry for %s has expired", u->nick, u->nick, iter->nickname.c_str());
			    iter = dl->erase(iter);
			}
			else
			{
			    ++iter;
			}
		    }
		}
	    }
	    else
	    {
		DELETE(dl);
		u->Shrink("dccallow_list");
		RemoveFromUserlist(u);
		ServerInstance->Log(DEBUG, "m_dccallow.so: UH OH! Couldn't get DCCALLOW list for %s", u->nick);
	    }
	}
    }

    void RemoveNick(userrec* user)
    {
	/* Iterate through all DCCALLOW lists and remove user */
	for (userlist::iterator iter = ul.begin(); iter != ul.end(); ++iter)
	{
	    userrec *u = (userrec*)(*iter);
	    u->GetExt("dccallow_list", dl);

	    if (dl)
	    {
		if (dl->size())
		{
		    for (dccallowlist::iterator i = dl->begin(); i != dl->end(); ++i)
		    {
			if (i->nickname == user->nick)
			{
			    
			    u->WriteServ("NOTICE %s :%s left the network or changed their nickname and has been removed from your DCCALLOW list", u->nick, i->nickname.c_str());
			    u->WriteServ("995 %s %s :Removed %s from your DCCALLOW list", u->nick, u->nick, i->nickname.c_str());
			    dl->erase(i);
			    break;
			}
		    }
		}
	    }
	    else
	    {
		DELETE(dl);
		u->Shrink("dccallow_list");
		RemoveFromUserlist(u);
	    }
	}
    }

    void RemoveFromUserlist(userrec *user)
    {
	// remove user from userlist
	for (userlist::iterator j = ul.begin(); j != ul.end(); ++j)
	{
	    userrec* u = (userrec*)(*j);
	    if (u->nick == user->nick)
	    {
		ul.erase(j);
		break;
	    }
	}
    }

    void ReadFileConf()
    {
	bfl.clear();
	for (int i = 0; i < Conf->Enumerate("banfile"); i++)
	{
	    BannedFileList bf;
	    std::string fileglob = Conf->ReadValue("banfile", "pattern", i);
	    std::string action = Conf->ReadValue("banfile", "action", i);
	    bf.filemask = fileglob;
	    bf.action = action;
	    bfl.push_back(bf);
	}
    
    }

    virtual ~ModuleDCCAllow()
    {
    }

    virtual Version GetVersion()
    {
	return Version(1,0,0,0,VF_COMMON,API_VERSION);
    }
};

class ModuleDCCAllowFactory : public ModuleFactory
{
 public:
    ModuleDCCAllowFactory()
    {
    }

    ~ModuleDCCAllowFactory()
    {
    }

    virtual Module * CreateModule(InspIRCd* Me)
    {
	return new ModuleDCCAllow(Me);
    }

};

extern "C" void * init_module( void )
{
    return new ModuleDCCAllowFactory;
}