anope/src/users.c

/* Routines to maintain a list of online users.
 *
 * (C) 2003-2008 Anope Team
 * Contact us at info@anope.org
 *
 * Please read COPYING and README for further details.
 *
 * Based on the original code of Epona by Lara.
 * Based on the original code of Services by Andy Church.
 *
 * $Id$
 *
 */

#include "services.h"

#define HASH(nick)	(((nick)[0]&31)<<5 | ((nick)[1]&31))
User *userlist[1024];

#define HASH2(nick)	(((nick)[0]&31)<<5 | ((nick)[1]&31))

int32 usercnt = 0, opcnt = 0;
uint32 maxusercnt = 0;
time_t maxusertime;

/*************************************************************************/
/*************************************************************************/

User::User(const std::string &snick)
{
	User **list;
	// XXX: we could do well to steal CoreException from insp
	if (snick.empty())
		throw "what the craq, empty nick passed to constructor";

	// XXX: we should also duplicate-check here.

	/* we used to do this by calloc, no more. */
	this->next = NULL;
	this->prev = NULL;
	username = host = hostip = vhost = vident = realname = nickTrack = uid = NULL;
	server = NULL;
	na = NULL;
	chans = NULL;
	founder_chans = NULL;
	moduleData = NULL;
	timestamp = my_signon = svid = mode = invalid_pw_time = lastmemosend = lastnickreg = lastmail = 0;

	strscpy(this->nick, snick.c_str(), NICKMAX);
	list = &userlist[HASH(this->nick)];
	this->next = *list;

	if (*list)
		(*list)->prev = this;

	*list = this;

	this->na = findnick(snick);

	if (this->na)
		this->na->u = this;

	usercnt++;

	if (usercnt > maxusercnt)
	{
		maxusercnt = usercnt;
		maxusertime = time(NULL);
		if (LogMaxUsers)
			alog("user: New maximum user count: %d", maxusercnt);
	}

	this->isSuperAdmin = 0;	 /* always set SuperAdmin to 0 for new users */
	this->nickTrack = NULL;	 /* ensure no default tracking nick */
}

void User::SetNewNick(const std::string &newnick)
{
	User **list;
	int is_same;

	/* Sanity check to make sure we don't segfault */
	if (newnick.empty())
	{
		throw "User::SetNewNick() got a bad argument";
	}

	is_same = (!stricmp(this->nick, nick) ? 1 : 0);

	if (this->prev)
		this->prev->next = this->next;
	else
		userlist[HASH(this->nick)] = this->next;

	if (this->next)
		this->next->prev = this->prev;

	strscpy(this->nick, nick, NICKMAX);
	list = &userlist[HASH(this->nick)];
	this->next = *list;
	this->prev = NULL;

	if (*list)
		(*list)->prev = this;
	*list = this;

	/* Only if old and new nick aren't the same; no need to waste time */
	if (!is_same)
	{
		if (this->na)
			this->na->u = NULL;
		this->na = findnick(nick);
		if (this->na)
			this->na->u = this;
	}

	if (debug)
		alog("debug: %s changed nick to %s", this->nick, newnick.c_str());
}

void User::SetDisplayedHost(const std::string &shost)
{
	if (shost.empty())
		throw "empty host? in MY services? it seems it's more likely than I thought.";

	if (this->vhost)
		free(this->vhost);
	this->vhost = sstrdup(shost.c_str());

	if (debug)
		alog("debug: %s changed vhost to %s", this->nick, shost.c_str());

	update_host(this);
}

void User::SetIdent(const std::string &ident)
{
	if (ident.empty())
		throw "empty ident in SetIdent";

	if (this->vident)
		free(this->vident);
	this->vident = sstrdup(ident.c_str());

	if (debug)
		alog("debug: %s changed ident to %s", this->nick, username);

	update_host(this);
}

void User::SetRealname(const std::string &srealname)
{
	if (srealname.empty())
		throw "realname empty in SetRealname";

	if (this->realname)
		free(this->realname);
	this->realname = sstrdup(srealname.c_str());

	if (this->na && (nick_identified(this) ||
			(!(this->na->nc->flags & NI_SECURE) && nick_recognized(this))))
	{
		if (this->na->last_realname)
			free(this->na->last_realname);
		this->na->last_realname = sstrdup(srealname.c_str());
	}

	if (debug)
		alog("debug: %s changed realname to %s", this->nick, srealname.c_str());
}

User::~User()
{
	struct u_chanlist *c, *c2;
	struct u_chaninfolist *ci, *ci2;
	char *srealname;

	if (LogUsers)
	{
		srealname = normalizeBuffer(this->realname);

		if (ircd->vhost)
		{
			alog("LOGUSERS: %s (%s@%s => %s) (%s) left the network (%s).",
				this->nick, this->username, this->host,
				(this->vhost ? this->vhost : "(none)"), srealname, this->server->name);
		}
		else
		{
			alog("LOGUSERS: %s (%s@%s) (%s) left the network (%s).",
				this->nick, this->username, this->host,
				srealname, this->server->name);
		}

		free(srealname);
	}

	send_event(EVENT_USER_LOGOFF, 1, this->nick);

	if (debug >= 2)
		alog("debug: User::~User() called");

	usercnt--;

	if (is_oper(this))
		opcnt--;

	if (debug >= 2)
		alog("debug: User::~User(): free user data");

	free(this->username);
	free(this->host);

	if (this->vhost)
		free(this->vhost);
	if (this->vident)
		free(this->vident);
	if (this->uid)
		free(this->uid);

	Anope_Free(this->realname);
	Anope_Free(this->hostip);

	if (debug >= 2)
		alog("debug: User::~User(): remove from channels");

	c = this->chans;

	while (c)
	{
		c2 = c->next;
		chan_deluser(this, c->chan);
		free(c);
		c = c2;
	}

	/* Cancel pending nickname enforcers, etc */
	cancel_user(this);

	if (this->na)
		this->na->u = NULL;

	if (debug >= 2)
		alog("debug: User::~User(): free founder data");
	ci = this->founder_chans;
	while (ci)
	{
		ci2 = ci->next;
		free(ci);
		ci = ci2;
	}

	if (this->nickTrack)
		free(this->nickTrack);

	moduleCleanStruct(&this->moduleData);

	if (debug >= 2)
		alog("debug: User::~User(): delete from list");

	if (this->prev)
		this->prev->next = this->next;
	else
		userlist[HASH(this->nick)] = this->next;

	if (this->next)
		this->next->prev = this->prev;

	if (debug >= 2)
		alog("debug: User::~User() done");
}

void User::SendMessage(const char *source, const char *fmt, ...)
{
	va_list args;
	char buf[BUFSIZE];
	*buf = '\0';

	if (fmt)
	{
		va_start(args, fmt);
		vsnprintf(buf, BUFSIZE - 1, fmt, args);

		this->SendMessage(source, std::string(buf));

		va_end(args);
	}
}

void User::SendMessage(const char *source, const std::string &msg)
{
	/* Send privmsg instead of notice if:
	* - UsePrivmsg is enabled
	* - The user is not registered and NSDefMsg is enabled
	* - The user is registered and has set /ns set msg on
	*/
	if (UsePrivmsg &&
		((!this->na && NSDefFlags & NI_MSG) || (this->na && this->na->nc->flags & NI_MSG)))
	{
		ircdproto->SendPrivmsg(findbot(source), this->nick, msg.c_str());
	}
	else
	{
		ircdproto->SendNotice(findbot(source), this->nick, msg.c_str());
	}
}


/*************************************************************************/
/*************************************************************************/

/*
 * XXX: I don't like how this "smells". I think it belongs in NickAlias/NickCore.
 * -- w00t
 */
void update_host(User * user)
{
	if (user->na && (nick_identified(user)
					 || (!(user->na->nc->flags & NI_SECURE)
						 && nick_recognized(user)))) {
		if (user->na->last_usermask)
			free(user->na->last_usermask);

		user->na->last_usermask =
			(char *)smalloc(strlen(common_get_vident(user)) +
					strlen(common_get_vhost(user)) + 2);
		sprintf(user->na->last_usermask, "%s@%s", common_get_vident(user),
				common_get_vhost(user));
	}
}

/*************************************************************************/
/*************************************************************************/
/*************************************************************************/

/* Return statistics.  Pointers are assumed to be valid. */

void get_user_stats(long *nusers, long *memuse)
{
	long count = 0, mem = 0;
	int i;
	User *user;
	struct u_chanlist *uc;
	struct u_chaninfolist *uci;

	for (i = 0; i < 1024; i++) {
		for (user = userlist[i]; user; user = user->next) {
			count++;
			mem += sizeof(*user);
			if (user->username)
				mem += strlen(user->username) + 1;
			if (user->host)
				mem += strlen(user->host) + 1;
			if (ircd->vhost) {
				if (user->vhost)
					mem += strlen(user->vhost) + 1;
			}
			if (user->realname)
				mem += strlen(user->realname) + 1;
			if (user->server->name)
				mem += strlen(user->server->name) + 1;
			for (uc = user->chans; uc; uc = uc->next)
				mem += sizeof(*uc);
			for (uci = user->founder_chans; uci; uci = uci->next)
				mem += sizeof(*uci);
		}
	}
	*nusers = count;
	*memuse = mem;
}

/*************************************************************************/

/* Find a user by nick.  Return NULL if user could not be found. */

User *finduser(const char *nick)
{
	User *user;

	if (!nick || !*nick) {
		if (debug) {
			alog("debug: finduser() called with NULL values");
		}
		return NULL;
	}

	if (debug >= 3)
		alog("debug: finduser(%p)", nick);
	user = userlist[HASH(nick)];
	while (user && stricmp(user->nick, nick) != 0)
		user = user->next;
	if (debug >= 3)
		alog("debug: finduser(%s) -> 0x%p", nick, (void *) user);
	return user;
}


/*************************************************************************/

/* Iterate over all users in the user list.  Return NULL at end of list. */

static User *current;
static int next_index;

User *firstuser(void)
{
	next_index = 0;
	current = NULL;
	while (next_index < 1024 && current == NULL)
		current = userlist[next_index++];
	if (debug)
		alog("debug: firstuser() returning %s",
			 current ? current->nick : "NULL (end of list)");
	return current;
}

User *nextuser(void)
{
	if (current)
		current = current->next;
	if (!current && next_index < 1024) {
		while (next_index < 1024 && current == NULL)
			current = userlist[next_index++];
	}
	if (debug)
		alog("debug: nextuser() returning %s",
			 current ? current->nick : "NULL (end of list)");
	return current;
}

User *find_byuid(const char *uid)
{
	User *u, *next;

	if (!uid) {
		if (debug)
			alog("debug: find_byuid() called with NULL-value");
		return NULL;
	}

	u = first_uid();
	while (u) {
		next = next_uid();
		if (u->uid) {
			if (!stricmp(uid, u->uid)) {
				return u;
			}
		}
		u = next;
	}
	return NULL;
}

static User *current_uid;
static int next_index_uid;

User *first_uid(void)
{
	next_index_uid = 0;
	current_uid = NULL;
	while (next_index_uid < 1024 && current_uid == NULL) {
		current_uid = userlist[next_index_uid++];
	}
	if (debug >= 2) {
		alog("debug: first_uid() returning %s %s",
			 current_uid ? current_uid->nick : "NULL (end of list)",
			 current_uid ? current_uid->uid : "");
	}
	return current_uid;
}

User *next_uid(void)
{
	if (current_uid)
		current_uid = current_uid->next;
	if (!current_uid && next_index_uid < 1024) {
		while (next_index_uid < 1024 && current_uid == NULL)
			current_uid = userlist[next_index_uid++];
	}
	if (debug >= 2) {
		alog("debug: next_uid() returning %s %s",
			 current_uid ? current_uid->nick : "NULL (end of list)",
			 current_uid ? current_uid->uid : "");
	}
	return current_uid;
}

/*************************************************************************/
/*************************************************************************/

/* Handle a server NICK command. */

User *do_nick(const char *source, const char *nick, const char *username, const char *host,
			  const char *server, const char *realname, time_t ts, uint32 svid,
			  uint32 ip, const char *vhost, const char *uid)
{
	User *user = NULL;

	char *tmp = NULL;
	NickAlias *old_na;		  /* Old nick rec */
	int nc_changed = 1;		 /* Did nick core change? */
	int status = 0;			 /* Status to apply */
	char mask[USERMAX + HOSTMAX + 2];
	char *logrealname;

	if (!*source) {
		char ipbuf[16];
		struct in_addr addr;

		if (ircd->nickvhost) {
			if (vhost) {
				if (!strcmp(vhost, "*")) {
					vhost = NULL;
					if (debug)
						alog("debug: new user�with no vhost in NICK command: %s", nick);
				}
			}
		}

		/* This is a new user; create a User structure for it. */
		if (debug)
			alog("debug: new user: %s", nick);

		if (ircd->nickip) {
			addr.s_addr = htonl(ip);
			ntoa(addr, ipbuf, sizeof(ipbuf));
		}


		if (LogUsers) {
		/**
	 * Ugly swap routine for Flop's bug :)
 	 **/
			if (realname) {
				tmp = strchr(realname, '%');
				while (tmp) {
					*tmp = '-';
					tmp = strchr(realname, '%');
				}
			}
			logrealname = normalizeBuffer(realname);

		/**
	 * End of ugly swap
	 **/

			if (ircd->nickvhost) {
				if (ircd->nickip) {
					alog("LOGUSERS: %s (%s@%s => %s) (%s) [%s] connected to the network (%s).", nick, username, host, (vhost ? vhost : "none"), logrealname, ipbuf, server);
				} else {
					alog("LOGUSERS: %s (%s@%s => %s) (%s) connected to the network (%s).", nick, username, host, (vhost ? vhost : "none"), logrealname, server);
				}
			} else {
				if (ircd->nickip) {
					alog("LOGUSERS: %s (%s@%s) (%s) [%s] connected to the network (%s).", nick, username, host, logrealname, ipbuf, server);
				} else {
					alog("LOGUSERS: %s (%s@%s) (%s) connected to the network (%s).", nick, username, host, logrealname, server);
				}
			}
			Anope_Free(logrealname);
		}

		/* We used to ignore the ~ which a lot of ircd's use to indicate no
		 * identd response.  That caused channel bans to break, so now we
		 * just take what the server gives us.  People are still encouraged
		 * to read the RFCs and stop doing anything to usernames depending
		 * on the result of an identd lookup.
		 */

		/* First check for AKILLs. */
		/* DONT just return null if its an akill match anymore - yes its more efficent to, however, now that ircd's are
		 * starting to use things like E/F lines, we cant be 100% sure the client will be removed from the network :/
		 * as such, create a user_struct, and if the client is removed, we'll delete it again when the QUIT notice
		 * comes in from the ircd.
		 **/
		if (check_akill(nick, username, host, vhost, ipbuf)) {
/*			return NULL; */
		}

/**
 * DefCon AKILL system, if we want to akill all connecting user's here's where to do it
 * then force check_akill again on them...
 **/
		/* don't akill on netmerges -Certus */
		/* don't akill clients introduced by ulines. -Viper */
		if (is_sync(findserver(servlist, server))
			&& checkDefCon(DEFCON_AKILL_NEW_CLIENTS) && !is_ulined(server)) {
			strncpy(mask, "*@", 3);
			strncat(mask, host, HOSTMAX);
			alog("DEFCON: adding akill for %s", mask);
			add_akill(NULL, mask, s_OperServ,
					  time(NULL) + DefConAKILL,
					  DefConAkillReason ? DefConAkillReason :
					  "DEFCON AKILL");
			if (check_akill(nick, username, host, vhost, ipbuf)) {
/*			return NULL; */
			}
		}

		/* SGLINE */
		if (ircd->sgline) {
			if (check_sgline(nick, realname))
				return NULL;
		}

		/* SQLINE */
		if (ircd->sqline) {
			if (check_sqline(nick, 0))
				return NULL;
		}

		/* SZLINE */
		if (ircd->szline && ircd->nickip) {
			if (check_szline(nick, ipbuf))
				return NULL;
		}
		/* Now check for session limits */
		if (LimitSessions && !is_ulined(server)
			&& !add_session(nick, host, ipbuf))
			return NULL;

		/* Allocate User structure and fill it in. */
		user = new User(nick);
		user->username = sstrdup(username);
		user->host = sstrdup(host);
		user->server = findserver(servlist, server);
		user->realname = sstrdup(realname);
		user->timestamp = ts;
		user->my_signon = time(NULL);
		user->vhost = vhost ? sstrdup(vhost) : sstrdup(host);
		if (uid) {
			user->uid = sstrdup(uid);   /* p10/ts6 stuff */
		} else {
			user->uid = NULL;
		}
		user->vident = sstrdup(username);
		/* We now store the user's ip in the user_ struct,
		 * because we will use it in serveral places -- DrStein */
		if (ircd->nickip) {
			user->hostip = sstrdup(ipbuf);
		} else {
			user->hostip = NULL;
		}

		if (svid == 0) {
			display_news(user, NEWS_LOGON);
			display_news(user, NEWS_RANDOM);
		}

		if (svid == ts && user->na) {
			/* Timestamp and svid match, and nick is registered; automagically identify the nick */
			user->svid = svid;
			user->na->status |= NS_IDENTIFIED;
			check_memos(user);
			nc_changed = 0;

			/* Start nick tracking if available */
			if (NSNickTracking)
				nsStartNickTracking(user);

		} else if (svid != 1) {
			/* Resets the svid because it doesn't match */
			user->svid = 1;

			ircdproto->SendSVID(user->nick, user->timestamp);

		} else {
			user->svid = 1;
		}
		send_event(EVENT_NEWNICK, 1, nick);

	} else {
		/* An old user changing nicks. */
		if (UseTS6)
			user = find_byuid(source);

		if (!user)
			user = finduser(source);

		if (!user) {
			alog("user: NICK from nonexistent nick %s", source);
			return NULL;
		}
		user->isSuperAdmin = 0; /* Dont let people nick change and stay SuperAdmins */
		if (debug)
			alog("debug: %s changes nick to %s", source, nick);

		if (LogUsers) {
			logrealname = normalizeBuffer(user->realname);
			if (ircd->vhost) {
				alog("LOGUSERS: %s (%s@%s => %s) (%s) changed nick to %s (%s).", user->nick, user->username, user->host, (user->vhost ? user->vhost : "(none)"), logrealname, nick, user->server->name);
			} else {
				alog("LOGUSERS: %s (%s@%s) (%s) changed nick to %s (%s).",
					 user->nick, user->username, user->host, logrealname,
					 nick, user->server->name);
			}
			if (logrealname) {
				free(logrealname);
			}
		}

		user->timestamp = ts;

		if (stricmp(nick, user->nick) == 0) {
			/* No need to redo things */
			user->SetNewNick(nick);
			nc_changed = 0;
		} else {
			/* Update this only if nicks aren't the same */
			user->my_signon = time(NULL);

			old_na = user->na;
			if (old_na) {
				if (nick_recognized(user))
					user->na->last_seen = time(NULL);
				status = old_na->status & NS_TRANSGROUP;
				cancel_user(user);
			}

			user->SetNewNick(nick);
			send_event(EVENT_CHANGE_NICK, 1, nick);

			if ((old_na ? old_na->nc : NULL) ==
				(user->na ? user->na->nc : NULL))
				nc_changed = 0;

			if (!nc_changed && (user->na))
				user->na->status |= status;
			else {
				ircdproto->SendUnregisteredNick(user);
			}
		}

		if (ircd->sqline) {
			if (!is_oper(user) && check_sqline(user->nick, 1))
				return NULL;
		}

	}						   /* if (!*source) */

	/* Check for nick tracking to bypass identification */
	if (NSNickTracking && nsCheckNickTracking(user)) {
		user->na->status |= NS_IDENTIFIED;
		nc_changed = 0;
	}

	if (nc_changed || !nick_recognized(user)) {
		if (validate_user(user))
			check_memos(user);

	} else {
		if (nick_identified(user)) {
			char tsbuf[16];
			user->na->last_seen = time(NULL);

			if (user->na->last_usermask)
				free(user->na->last_usermask);
			user->na->last_usermask =
				(char *)smalloc(strlen(common_get_vident(user)) +
						strlen(common_get_vhost(user)) + 2);
			sprintf(user->na->last_usermask, "%s@%s",
					common_get_vident(user), common_get_vhost(user));

			snprintf(tsbuf, sizeof(tsbuf), "%lu",
					 (unsigned long int) user->timestamp);
			ircdproto->SendSVID2(user, tsbuf);

			alog("%s: %s!%s@%s automatically identified for nick %s",
				 s_NickServ, user->nick, user->username,
				 user->host, user->nick);
		}
	}

	/* Bahamut sets -r on every nick changes, so we must test it even if nc_changed == 0 */
	if (ircd->check_nick_id) {
		if (nick_identified(user)) {
			char tsbuf[16];
			snprintf(tsbuf, sizeof(tsbuf), "%lu",
					 (unsigned long int) user->timestamp);
			ircdproto->SendSVID3(user, tsbuf);
		}
	}

	return user;
}

/*************************************************************************/

/* Handle a MODE command for a user.
 *	av[0] = nick to change mode for
 *	av[1] = modes
 */

void do_umode(const char *source, int ac, const char **av)
{
	User *user;

	user = finduser(av[0]);
	if (!user) {
		alog("user: MODE %s for nonexistent nick %s: %s", av[1], av[0],
			 merge_args(ac, av));
		return;
	}

	ircdproto->ProcessUsermodes(user, ac - 1, &av[1]);
}

/* Handle a UMODE2 command for a user.
 *	av[0] = modes
 */

void do_umode2(const char *source, int ac, const char **av)
{
	User *user;

	user = finduser(source);
	if (!user) {
		alog("user: MODE %s for nonexistent nick %s: %s", av[0], source,
			 merge_args(ac, av));
		return;
	}

	ircdproto->ProcessUsermodes(user, ac, &av[0]);
}

/*************************************************************************/

/* Handle a QUIT command.
 *	av[0] = reason
 */

void do_quit(const char *source, int ac, const char **av)
{
	User *user;
	NickAlias *na;

	user = finduser(source);
	if (!user) {
		alog("user: QUIT from nonexistent user %s: %s", source,
			 merge_args(ac, av));
		return;
	}
	if (debug) {
		alog("debug: %s quits", source);
	}
	if ((na = user->na) && (!(na->status & NS_VERBOTEN))
		&& (!(na->nc->flags & NI_SUSPENDED))
		&& (na->status & (NS_IDENTIFIED | NS_RECOGNIZED))) {
		na->last_seen = time(NULL);
		if (na->last_quit)
			free(na->last_quit);
		na->last_quit = *av[0] ? sstrdup(av[0]) : NULL;
	}
	if (LimitSessions && !is_ulined(user->server->name)) {
		del_session(user->host);
	}
	delete user;
}

/*************************************************************************/

/* Handle a KILL command.
 *	av[0] = nick being killed
 *	av[1] = reason
 */

void do_kill(const char *nick, const char *msg)
{
	User *user;
	NickAlias *na;

	user = finduser(nick);
	if (!user) {
		if (debug) {
			alog("debug: KILL of nonexistent nick: %s", nick);
		}
		return;
	}
	if (debug) {
		alog("debug: %s killed", nick);
	}
	if ((na = user->na) && (!(na->status & NS_VERBOTEN))
		&& (!(na->nc->flags & NI_SUSPENDED))
		&& (na->status & (NS_IDENTIFIED | NS_RECOGNIZED))) {
		na->last_seen = time(NULL);
		if (na->last_quit)
			free(na->last_quit);
		na->last_quit = *msg ? sstrdup(msg) : NULL;

	}
	if (LimitSessions && !is_ulined(user->server->name)) {
		del_session(user->host);
	}
	delete user;
}

/*************************************************************************/
/*************************************************************************/

/* Is the given user protected from kicks and negative mode changes? */

int is_protected(User * user)
{
	if (ircd->protectedumode) {
		return (user->mode & ircd->protectedumode);
	} else {
		return 0;
	}
}

/*************************************************************************/

/* Is the given nick an oper? */

int is_oper(User * user)
{
	if (user) {
		return (user->mode & anope_get_oper_mode());
	} else {
		return 0;
	}
}

/*************************************************************************/
/*************************************************************************/

/* Is the given user ban-excepted? */
int is_excepted(ChannelInfo * ci, User * user)
{
	if (!ci->c || !ircd->except)
		return 0;

	if (elist_match_user(ci->c->excepts, user))
		return 1;

	return 0;
}

/*************************************************************************/

/* Is the given MASK ban-excepted? */
int is_excepted_mask(ChannelInfo * ci, char *mask)
{
	if (!ci->c || !ircd->except)
		return 0;

	if (elist_match_mask(ci->c->excepts, mask, 0))
		return 1;

	return 0;
}


/*************************************************************************/

/* Does the user's usermask match the given mask (either nick!user@host or
 * just user@host)?
 */

int match_usermask(const char *mask, User * user)
{
	char *mask2;
	char *nick, *username, *host;
	int result;

	if (!mask || !*mask) {
		return 0;
	}

	mask2 = sstrdup(mask);

	if (strchr(mask2, '!')) {
		nick = strtok(mask2, "!");
		username = strtok(NULL, "@");
	} else {
		nick = NULL;
		username = strtok(mask2, "@");
	}
	host = strtok(NULL, "");
	if (!username || !host) {
		free(mask2);
		return 0;
	}

	if (nick) {
		result = match_wild_nocase(nick, user->nick)
			&& match_wild_nocase(username, user->username)
			&& (match_wild_nocase(host, user->host)
				|| match_wild_nocase(host, user->vhost));
	} else {
		result = match_wild_nocase(username, user->username)
			&& (match_wild_nocase(host, user->host)
				|| match_wild_nocase(host, user->vhost));
	}

	free(mask2);
	return result;
}


/*************************************************************************/

/* simlar to match_usermask, except here we pass the host as the IP */

int match_userip(const char *mask, User * user, char *iphost)
{
	char *mask2;
	char *nick, *username, *host;
	int result;

	if (!mask || !*mask) {
		return 0;
	}

	mask2 = sstrdup(mask);

	if (strchr(mask2, '!')) {
		nick = strtok(mask2, "!");
		username = strtok(NULL, "@");
	} else {
		nick = NULL;
		username = strtok(mask2, "@");
	}
	host = strtok(NULL, "");
	if (!username || !host) {
		free(mask2);
		return 0;
	}

	if (nick) {
		result = match_wild_nocase(nick, user->nick)
			&& match_wild_nocase(username, user->username)
			&& (match_wild_nocase(host, iphost)
				|| match_wild_nocase(host, user->vhost));
	} else {
		result = match_wild_nocase(username, user->username)
			&& (match_wild_nocase(host, iphost)
				|| match_wild_nocase(host, user->vhost));
	}

	free(mask2);
	return result;
}

/*************************************************************************/

/* Split a usermask up into its constitutent parts.  Returned strings are
 * malloc()'d, and should be free()'d when done with.  Returns "*" for
 * missing parts.
 */

void split_usermask(const char *mask, char **nick, char **user,
					char **host)
{
	char *mask2 = sstrdup(mask);

	*nick = strtok(mask2, "!");
	*user = strtok(NULL, "@");
	*host = strtok(NULL, "");
	/* Handle special case: mask == user@host */
	if (*nick && !*user && strchr(*nick, '@')) {
		*nick = NULL;
		*user = strtok(mask2, "@");
		*host = strtok(NULL, "");
	}
	if (!*nick)
		*nick = "*";
	if (!*user)
		*user = "*";
	if (!*host)
		*host = "*";
	*nick = sstrdup(*nick);
	*user = sstrdup(*user);
	*host = sstrdup(*host);
	free(mask2);
}

/*************************************************************************/

/* Given a user, return a mask that will most likely match any address the
 * user will have from that location.  For IP addresses, wildcards the
 * appropriate subnet mask (e.g. 35.1.1.1 -> 35.*; 128.2.1.1 -> 128.2.*);
 * for named addresses, wildcards the leftmost part of the name unless the
 * name only contains two parts.  If the username begins with a ~, delete
 * it.  The returned character string is malloc'd and should be free'd
 * when done with.
 */

char *create_mask(User * u)
{
	char *mask, *s, *end;
	int ulen = strlen(common_get_vident(u));

	/* Get us a buffer the size of the username plus hostname.  The result
	 * will never be longer than this (and will often be shorter), thus we
	 * can use strcpy() and sprintf() safely.
	 */
	end = mask = (char *)smalloc(ulen + strlen(common_get_vhost(u)) + 3);
	end += sprintf(end, "%s%s@",
				   (ulen <
					(*(common_get_vident(u)) ==
					 '~' ? USERMAX + 1 : USERMAX) ? "*" : ""),
				   (*(common_get_vident(u)) ==
					'~' ? common_get_vident(u) +
					1 : common_get_vident(u)));

	if (strspn(common_get_vhost(u), "0123456789.") ==
		strlen(common_get_vhost(u))
		&& (s = strchr(common_get_vhost(u), '.'))
		&& (s = strchr(s + 1, '.'))
		&& (s = strchr(s + 1, '.'))
		&& (!strchr(s + 1, '.'))) {	 /* IP addr */
		s = sstrdup(common_get_vhost(u));
		*strrchr(s, '.') = 0;

		sprintf(end, "%s.*", s);
		free(s);
	} else {
		if ((s = strchr(common_get_vhost(u), '.')) && strchr(s + 1, '.')) {
			s = sstrdup(strchr(common_get_vhost(u), '.') - 1);
			*s = '*';
			strcpy(end, s);
			free(s);
		} else {
			strcpy(end, common_get_vhost(u));
		}
	}
	return mask;
}

/*************************************************************************/