ip_irc_pxy.c - net/ipfilter - Rivoreo Source Code Repositories

 /*
  * Copyright (C) 2000-2003 Darren Reed
  *
  * See the IPFILTER.LICENCE file for details on licencing.
  *
  * $Id$
  */

 #define	IPF_IRC_PROXY

 #define	IPF_IRCBUFSZ	96	/* This *MUST* be >= 64! */


 void ipf_p_irc_main_load __P((void));
 void ipf_p_irc_main_unload __P((void));
 int ipf_p_irc_new __P((void *, fr_info_t *, ap_session_t *, nat_t *));
 int ipf_p_irc_out __P((void *, fr_info_t *, ap_session_t *, nat_t *));
 int ipf_p_irc_send __P((fr_info_t *, nat_t *));
 int ipf_p_irc_complete __P((ircinfo_t *, char *, size_t));
 u_short ipf_irc_atoi __P((char **));

 static	frentry_t	ircnatfr;

 int	irc_proxy_init = 0;


 /*
  * Initialize local structures.
  */
 void
 ipf_p_irc_main_load()
 {
 	bzero((char *)&ircnatfr, sizeof(ircnatfr));
 	ircnatfr.fr_ref = 1;
 	ircnatfr.fr_flags = FR_INQUE|FR_PASS|FR_QUICK|FR_KEEPSTATE;
 	MUTEX_INIT(&ircnatfr.fr_lock, "IRC proxy rule lock");
 	irc_proxy_init = 1;
 }


 void
 ipf_p_irc_main_unload()
 {
 	if (irc_proxy_init == 1) {
 		MUTEX_DESTROY(&ircnatfr.fr_lock);
 		irc_proxy_init = 0;
 	}
 }


 const char *ipf_p_irc_dcctypes[] = {
 	"CHAT ",	/* CHAT chat ipnumber portnumber */
 	"SEND ",	/* SEND filename ipnumber portnumber */
 	"MOVE ",
 	"TSEND ",
 	"SCHAT ",
 	NULL,
 };


 /*
  * :A PRIVMSG B :^ADCC CHAT chat 0 0^A\r\n
  * PRIVMSG B ^ADCC CHAT chat 0 0^A\r\n
  */


 int
 ipf_p_irc_complete(ircp, buf, len)
 	ircinfo_t *ircp;
 	char *buf;
 	size_t len;
 {
 	register char *s, c;
 	register size_t i;
 	u_32_t l;
 	int j, k;

 	ircp->irc_ipnum = 0;
 	ircp->irc_port = 0;

 	if (len < 31)
 		return 0;
 	s = buf;
 	c = *s++;
 	i = len - 1;

 	if ((c != ':') && (c != 'P'))
 		return 0;

 	if (c == ':') {
 		/*
 		 * Loosely check that the source is a nickname of some sort
 		 */
 		s++;
 		c = *s;
 		ircp->irc_snick = s;
 		if (!ISALPHA(c))
 			return 0;
 		i--;
 		for (c = *s; !ISSPACE(c) && (i > 0); i--)
 			c = *s++;
 		if (i < 31)
 			return 0;
 		if (c != 'P')
 			return 0;
 	} else
 		ircp->irc_snick = NULL;

 	/*
 	 * Check command string
 	 */
 	if (strncmp(s, "PRIVMSG ", 8))
 		return 0;
 	i -= 8;
 	s += 8;
 	c = *s;
 	ircp->irc_dnick = s;

 	/*
 	 * Loosely check that the destination is a nickname of some sort
 	 */
 	if (!ISALPHA(c))
 		return 0;
 	for (; !ISSPACE(c) && (i > 0); i--)
 		c = *s++;
 	if (i < 20)
 		return 0;
 	s++,
 	i--;

 	/*
 	 * Look for a ^A to start the DCC
 	 */
 	c = *s;
 	if (c == ':') {
 		s++;
 		c = *s;
 	}

 	if (strncmp(s, "\001DCC ", 4))
 		return 0;

 	i -= 4;
 	s += 4;

 	/*
 	 * Check for a recognised DCC command
 	 */
 	for (j = 0, k = 0; ipf_p_irc_dcctypes[j]; j++) {
 		k = MIN(strlen(ipf_p_irc_dcctypes[j]), i);
 		if (!strncmp(ipf_p_irc_dcctypes[j], s, k))
 			break;
 	}
 	if (!ipf_p_irc_dcctypes[j])
 		return 0;

 	ircp->irc_type = s;
 	i -= k;
 	s += k;

 	if (i < 11)
 		return 0;

 	/*
 	 * Check for the arg
 	 */
 	c = *s;
 	if (ISSPACE(c))
 		return 0;
 	ircp->irc_arg = s;
 	for (; (c != ' ') && (c != '\001') && (i > 0); i--)
 		c = *s++;

 	if (c == '\001')	/* In reality a ^A can quote another ^A...*/
 		return 0;

 	if (i < 5)
 		return 0;

 	s++;
 	i--;
 	c = *s;
 	if (!ISDIGIT(c))
 		return 0;
 	ircp->irc_addr = s;
 	/*
 	 * Get the IP#
 	 */
 	for (l = 0; ISDIGIT(c) && (i > 0); i--) {
 		l *= 10;
 		l += c - '0';
 		c = *s++;
 	}

 	if (i < 4)
 		return 0;

 	if (c != ' ')
 		return 0;

 	ircp->irc_ipnum = l;
 	s++;
 	i--;
 	c = *s;
 	if (!ISDIGIT(c))
 		return 0;
 	/*
 	 * Get the port#
 	 */
 	for (l = 0; ISDIGIT(c) && (i > 0); i--) {
 		l *= 10;
 		l += c - '0';
 		c = *s++;
 	}
 	if (i < 3)
 		return 0;
 	if (strncmp(s, "\001\r\n", 3))
 		return 0;
 	s += 3;
 	ircp->irc_len = s - buf;
 	ircp->irc_port = l;
 	return 1;
 }


 int
 ipf_p_irc_new(arg, fin, aps, nat)
 	void *arg;
 	fr_info_t *fin;
 	ap_session_t *aps;
 	nat_t *nat;
 {
 	ircinfo_t *irc;

 	KMALLOC(irc, ircinfo_t *);
 	if (irc == NULL)
 		return -1;

 	fin = fin;	/* LINT */
 	nat = nat;	/* LINT */

 	aps->aps_data = irc;
 	aps->aps_psiz = sizeof(ircinfo_t);

 	bzero((char *)irc, sizeof(*irc));
 	return 0;
 }


 int
 ipf_p_irc_send(fin, nat)
 	fr_info_t *fin;
 	nat_t *nat;
 {
 	char ctcpbuf[IPF_IRCBUFSZ], newbuf[IPF_IRCBUFSZ];
 	tcphdr_t *tcp, tcph, *tcp2 = &tcph;
 	int off, inc = 0, i, dlen;
 	ipf_main_softc_t *softc;
 	size_t nlen = 0, olen;
 	struct in_addr swip;
 	u_short a5, sp;
 	ircinfo_t *irc;
 	fr_info_t fi;
 	nat_t *nat2;
 	u_int a1;
 	ip_t *ip;
 	mb_t *m;
 #ifdef	MENTAT
 	mb_t *m1;
 #endif
 	softc = fin->fin_main_soft;

 	m = fin->fin_m;
 	ip = fin->fin_ip;
 	tcp = (tcphdr_t *)fin->fin_dp;
 	bzero(ctcpbuf, sizeof(ctcpbuf));
 	off = (char *)tcp - (char *)ip + (TCP_OFF(tcp) << 2) + fin->fin_ipoff;

 #ifdef __sgi
 	dlen = fin->fin_plen - off;
 #else
 	dlen = MSGDSIZE(m) - off;
 #endif
 	if (dlen <= 0)
 		return 0;
 	COPYDATA(m, off, MIN(sizeof(ctcpbuf), dlen), ctcpbuf);

 	if (dlen <= 0)
 		return 0;
 	ctcpbuf[sizeof(ctcpbuf) - 1] = '\0';
 	*newbuf = '\0';

 	irc = nat->nat_aps->aps_data;
 	if (ipf_p_irc_complete(irc, ctcpbuf, dlen) == 0)
 		return 0;

 	/*
 	 * check that IP address in the DCC reply is the same as the
 	 * sender of the command - prevents use for port scanning.
 	 */
 	if (irc->irc_ipnum != ntohl(nat->nat_osrcaddr))
 		return 0;

 	a5 = irc->irc_port;

 	/*
 	 * Calculate new address parts for the DCC command
 	 */
 	a1 = ntohl(ip->ip_src.s_addr);
 	olen = irc->irc_len;
 	i = irc->irc_addr - ctcpbuf;
 	i++;
 	(void) strncpy(newbuf, ctcpbuf, i);
 	/* DO NOT change these! */
 #if defined(SNPRINTF) && defined(KERNEL)
 	SNPRINTF(newbuf, sizeof(newbuf) - i, "%u %u\001\r\n", a1, a5);
 #else
 	(void) sprintf(newbuf, "%u %u\001\r\n", a1, a5);
 #endif

 	nlen = strlen(newbuf);
 	inc = nlen - olen;

 	if ((inc + fin->fin_plen) > 65535)
 		return 0;

 #ifdef	MENTAT
 	for (m1 = m; m1->b_cont; m1 = m1->b_cont)
 		;
 	if ((inc > 0) && (m1->b_datap->db_lim - m1->b_wptr < inc)) {
 		mblk_t *nm;

 		/* alloc enough to keep same trailer space for lower driver */
 		nm = allocb(nlen, BPRI_MED);
 		PANIC((!nm),("ipf_p_irc_out: allocb failed"));

 		nm->b_band = m1->b_band;
 		nm->b_wptr += nlen;

 		m1->b_wptr -= olen;
 		PANIC((m1->b_wptr < m1->b_rptr),
 		      ("ipf_p_irc_out: cannot handle fragmented data block"));

 		linkb(m1, nm);
 	} else {
 # if SOLARIS && defined(ICK_VALID)
 		if (m1->b_datap->db_struiolim == m1->b_wptr)
 			m1->b_datap->db_struiolim += inc;
 		m1->b_datap->db_struioflag &= ~STRUIO_IP;
 # endif
 		m1->b_wptr += inc;
 	}
 #else
 	if (inc < 0)
 		m_adj(m, inc);
 	/* the mbuf chain will be extended if necessary by m_copyback() */
 #endif
 	COPYBACK(m, off, nlen, newbuf);

 	if (inc != 0) {
 #if defined(MENTAT) || defined(__sgi)
 		register u_32_t	sum1, sum2;

 		sum1 = fin->fin_plen;
 		sum2 = fin->fin_plen + inc;

 		/* Because ~1 == -2, We really need ~1 == -1 */
 		if (sum1 > sum2)
 			sum2--;
 		sum2 -= sum1;
 		sum2 = (sum2 & 0xffff) + (sum2 >> 16);

 		ipf_fix_outcksum(fin, &ip->ip_sum, sum2);
 #endif
 		fin->fin_plen += inc;
 		ip->ip_len = htons(fin->fin_plen);
 		fin->fin_dlen += inc;
 	}

 	/*
 	 * Add skeleton NAT entry for connection which will come back the
 	 * other way.
 	 */
 	sp = htons(a5);
 	/*
 	 * Don't allow the PORT command to specify a port < 1024 due to
 	 * security crap.
 	 */
 	if (ntohs(sp) < 1024)
 		return 0;

 	/*
 	 * The server may not make the connection back from port 20, but
 	 * it is the most likely so use it here to check for a conflicting
 	 * mapping.
 	 */
 	bcopy((caddr_t)fin, (caddr_t)&fi, sizeof(fi));
 	fi.fin_data[0] = sp;
 	fi.fin_data[1] = fin->fin_data[1];
 	nat2 = ipf_nat_outlookup(fin, IPN_TCP, nat->nat_pr[1], nat->nat_nsrcip,
 			     ip->ip_dst);
 	if (nat2 == NULL) {
 #ifdef USE_MUTEXES
 		ipf_nat_softc_t *softn = softc->ipf_nat_soft;
 #endif

 		bcopy((caddr_t)fin, (caddr_t)&fi, sizeof(fi));
 		bzero((char *)tcp2, sizeof(*tcp2));
 		tcp2->th_win = htons(8192);
 		tcp2->th_sport = sp;
 		tcp2->th_dport = 0; /* XXX - don't specify remote port */
 		fi.fin_state = NULL;
 		fi.fin_nat = NULL;
 		fi.fin_data[0] = ntohs(sp);
 		fi.fin_data[1] = 0;
 		fi.fin_dp = (char *)tcp2;
 		fi.fin_fr = &ircnatfr;
 		fi.fin_dlen = sizeof(*tcp2);
 		fi.fin_plen = fi.fin_hlen + sizeof(*tcp2);
 		swip = ip->ip_src;
 		ip->ip_src = nat->nat_nsrcip;
 		MUTEX_ENTER(&softn->ipf_nat_new);
 		nat2 = ipf_nat_add(&fi, nat->nat_ptr, NULL,
 			       NAT_SLAVE|IPN_TCP|SI_W_DPORT, NAT_OUTBOUND);
 		MUTEX_EXIT(&softn->ipf_nat_new);
 		if (nat2 != NULL) {
 			(void) ipf_nat_proto(&fi, nat2, 0);
 			MUTEX_ENTER(&nat2->nat_lock);
 			ipf_nat_update(&fi, nat2);
 			MUTEX_EXIT(&nat2->nat_lock);

 			if (ipf_state_add(softc, &fi, &fi.fin_state,
 					  SI_W_DPORT) == 0)
 				ipf_state_deref(softc,
 						(ipstate_t **)&fi.fin_state);
 		}
 		ip->ip_src = swip;
 	}
 	return inc;
 }


 int
 ipf_p_irc_out(arg, fin, aps, nat)
 	void *arg;
 	fr_info_t *fin;
 	ap_session_t *aps;
 	nat_t *nat;
 {
 	aps = aps;	/* LINT */
 	return ipf_p_irc_send(fin, nat);
 }
	/*
	* Copyright (C) 2000-2003 Darren Reed
	*
	* See the IPFILTER.LICENCE file for details on licencing.
	*
	* $Id$
	*/

	#define IPF_IRC_PROXY

	#define IPF_IRCBUFSZ 96 /* This MUST be >= 64! */


	void ipf_p_irc_main_load __P((void));
	void ipf_p_irc_main_unload __P((void));
	int ipf_p_irc_new __P((void , fr_info_t , ap_session_t , nat_t ));
	int ipf_p_irc_out __P((void , fr_info_t , ap_session_t , nat_t ));
	int ipf_p_irc_send __P((fr_info_t , nat_t ));
	int ipf_p_irc_complete __P((ircinfo_t , char , size_t));
	u_short ipf_irc_atoi __P((char **));

	static frentry_t ircnatfr;

	int irc_proxy_init = 0;


	/*
	* Initialize local structures.
	*/
	void
	ipf_p_irc_main_load()
	{
	bzero((char *)&ircnatfr, sizeof(ircnatfr));
	ircnatfr.fr_ref = 1;
	ircnatfr.fr_flags = FR_INQUE\|FR_PASS\|FR_QUICK\|FR_KEEPSTATE;
	MUTEX_INIT(&ircnatfr.fr_lock, "IRC proxy rule lock");
	irc_proxy_init = 1;
	}


	void
	ipf_p_irc_main_unload()
	{
	if (irc_proxy_init == 1) {
	MUTEX_DESTROY(&ircnatfr.fr_lock);
	irc_proxy_init = 0;
	}
	}


	const char *ipf_p_irc_dcctypes[] = {
	"CHAT ", /* CHAT chat ipnumber portnumber */
	"SEND ", /* SEND filename ipnumber portnumber */
	"MOVE ",
	"TSEND ",
	"SCHAT ",
	NULL,
	};


	/*
	* :A PRIVMSG B :^ADCC CHAT chat 0 0^A\r\n
	* PRIVMSG B ^ADCC CHAT chat 0 0^A\r\n
	*/


	int
	ipf_p_irc_complete(ircp, buf, len)
	ircinfo_t *ircp;
	char *buf;
	size_t len;
	{
	register char *s, c;
	register size_t i;
	u_32_t l;
	int j, k;

	ircp->irc_ipnum = 0;
	ircp->irc_port = 0;

	if (len < 31)
	return 0;
	s = buf;
	c = *s++;
	i = len - 1;

	if ((c != ':') && (c != 'P'))
	return 0;

	if (c == ':') {
	/*
	* Loosely check that the source is a nickname of some sort
	*/
	s++;
	c = *s;
	ircp->irc_snick = s;
	if (!ISALPHA(c))
	return 0;
	i--;
	for (c = *s; !ISSPACE(c) && (i > 0); i--)
	c = *s++;
	if (i < 31)
	return 0;
	if (c != 'P')
	return 0;
	} else
	ircp->irc_snick = NULL;

	/*
	* Check command string
	*/
	if (strncmp(s, "PRIVMSG ", 8))
	return 0;
	i -= 8;
	s += 8;
	c = *s;
	ircp->irc_dnick = s;

	/*
	* Loosely check that the destination is a nickname of some sort
	*/
	if (!ISALPHA(c))
	return 0;
	for (; !ISSPACE(c) && (i > 0); i--)
	c = *s++;
	if (i < 20)
	return 0;
	s++,
	i--;

	/*
	* Look for a ^A to start the DCC
	*/
	c = *s;
	if (c == ':') {
	s++;
	c = *s;
	}

	if (strncmp(s, "\001DCC ", 4))
	return 0;

	i -= 4;
	s += 4;

	/*
	* Check for a recognised DCC command
	*/
	for (j = 0, k = 0; ipf_p_irc_dcctypes[j]; j++) {
	k = MIN(strlen(ipf_p_irc_dcctypes[j]), i);
	if (!strncmp(ipf_p_irc_dcctypes[j], s, k))
	break;
	}
	if (!ipf_p_irc_dcctypes[j])
	return 0;

	ircp->irc_type = s;
	i -= k;
	s += k;

	if (i < 11)
	return 0;

	/*
	* Check for the arg
	*/
	c = *s;
	if (ISSPACE(c))
	return 0;
	ircp->irc_arg = s;
	for (; (c != ' ') && (c != '\001') && (i > 0); i--)
	c = *s++;

	if (c == '\001') /* In reality a ^A can quote another ^A...*/
	return 0;

	if (i < 5)
	return 0;

	s++;
	i--;
	c = *s;
	if (!ISDIGIT(c))
	return 0;
	ircp->irc_addr = s;
	/*
	* Get the IP#
	*/
	for (l = 0; ISDIGIT(c) && (i > 0); i--) {
	l *= 10;
	l += c - '0';
	c = *s++;
	}

	if (i < 4)
	return 0;

	if (c != ' ')
	return 0;

	ircp->irc_ipnum = l;
	s++;
	i--;
	c = *s;
	if (!ISDIGIT(c))
	return 0;
	/*
	* Get the port#
	*/
	for (l = 0; ISDIGIT(c) && (i > 0); i--) {
	l *= 10;
	l += c - '0';
	c = *s++;
	}
	if (i < 3)
	return 0;
	if (strncmp(s, "\001\r\n", 3))
	return 0;
	s += 3;
	ircp->irc_len = s - buf;
	ircp->irc_port = l;
	return 1;
	}


	int
	ipf_p_irc_new(arg, fin, aps, nat)
	void *arg;
	fr_info_t *fin;
	ap_session_t *aps;
	nat_t *nat;
	{
	ircinfo_t *irc;

	KMALLOC(irc, ircinfo_t *);
	if (irc == NULL)
	return -1;

	fin = fin; /* LINT */
	nat = nat; /* LINT */

	aps->aps_data = irc;
	aps->aps_psiz = sizeof(ircinfo_t);

	bzero((char )irc, sizeof(irc));
	return 0;
	}


	int
	ipf_p_irc_send(fin, nat)
	fr_info_t *fin;
	nat_t *nat;
	{
	char ctcpbuf[IPF_IRCBUFSZ], newbuf[IPF_IRCBUFSZ];
	tcphdr_t tcp, tcph, tcp2 = &tcph;
	int off, inc = 0, i, dlen;
	ipf_main_softc_t *softc;
	size_t nlen = 0, olen;
	struct in_addr swip;
	u_short a5, sp;
	ircinfo_t *irc;
	fr_info_t fi;
	nat_t *nat2;
	u_int a1;
	ip_t *ip;
	mb_t *m;
	#ifdef MENTAT
	mb_t *m1;
	#endif
	softc = fin->fin_main_soft;

	m = fin->fin_m;
	ip = fin->fin_ip;
	tcp = (tcphdr_t *)fin->fin_dp;
	bzero(ctcpbuf, sizeof(ctcpbuf));
	off = (char )tcp - (char )ip + (TCP_OFF(tcp) << 2) + fin->fin_ipoff;

	#ifdef __sgi
	dlen = fin->fin_plen - off;
	#else
	dlen = MSGDSIZE(m) - off;
	#endif
	if (dlen <= 0)
	return 0;
	COPYDATA(m, off, MIN(sizeof(ctcpbuf), dlen), ctcpbuf);

	if (dlen <= 0)
	return 0;
	ctcpbuf[sizeof(ctcpbuf) - 1] = '\0';
	*newbuf = '\0';

	irc = nat->nat_aps->aps_data;
	if (ipf_p_irc_complete(irc, ctcpbuf, dlen) == 0)
	return 0;

	/*
	* check that IP address in the DCC reply is the same as the
	* sender of the command - prevents use for port scanning.
	*/
	if (irc->irc_ipnum != ntohl(nat->nat_osrcaddr))
	return 0;

	a5 = irc->irc_port;

	/*
	* Calculate new address parts for the DCC command
	*/
	a1 = ntohl(ip->ip_src.s_addr);
	olen = irc->irc_len;
	i = irc->irc_addr - ctcpbuf;
	i++;
	(void) strncpy(newbuf, ctcpbuf, i);
	/* DO NOT change these! */
	#if defined(SNPRINTF) && defined(KERNEL)
	SNPRINTF(newbuf, sizeof(newbuf) - i, "%u %u\001\r\n", a1, a5);
	#else
	(void) sprintf(newbuf, "%u %u\001\r\n", a1, a5);
	#endif

	nlen = strlen(newbuf);
	inc = nlen - olen;

	if ((inc + fin->fin_plen) > 65535)
	return 0;

	#ifdef MENTAT
	for (m1 = m; m1->b_cont; m1 = m1->b_cont)
	;
	if ((inc > 0) && (m1->b_datap->db_lim - m1->b_wptr < inc)) {
	mblk_t *nm;

	/* alloc enough to keep same trailer space for lower driver */
	nm = allocb(nlen, BPRI_MED);
	PANIC((!nm),("ipf_p_irc_out: allocb failed"));

	nm->b_band = m1->b_band;
	nm->b_wptr += nlen;

	m1->b_wptr -= olen;
	PANIC((m1->b_wptr < m1->b_rptr),
	("ipf_p_irc_out: cannot handle fragmented data block"));

	linkb(m1, nm);
	} else {
	# if SOLARIS && defined(ICK_VALID)
	if (m1->b_datap->db_struiolim == m1->b_wptr)
	m1->b_datap->db_struiolim += inc;
	m1->b_datap->db_struioflag &= ~STRUIO_IP;
	# endif
	m1->b_wptr += inc;
	}
	#else
	if (inc < 0)
	m_adj(m, inc);
	/* the mbuf chain will be extended if necessary by m_copyback() */
	#endif
	COPYBACK(m, off, nlen, newbuf);

	if (inc != 0) {
	#if defined(MENTAT) \|\| defined(__sgi)
	register u_32_t sum1, sum2;

	sum1 = fin->fin_plen;
	sum2 = fin->fin_plen + inc;

	/* Because ~1 == -2, We really need ~1 == -1 */
	if (sum1 > sum2)
	sum2--;
	sum2 -= sum1;
	sum2 = (sum2 & 0xffff) + (sum2 >> 16);

	ipf_fix_outcksum(fin, &ip->ip_sum, sum2);
	#endif
	fin->fin_plen += inc;
	ip->ip_len = htons(fin->fin_plen);
	fin->fin_dlen += inc;
	}

	/*
	* Add skeleton NAT entry for connection which will come back the
	* other way.
	*/
	sp = htons(a5);
	/*
	* Don't allow the PORT command to specify a port < 1024 due to
	* security crap.
	*/
	if (ntohs(sp) < 1024)
	return 0;

	/*
	* The server may not make the connection back from port 20, but
	* it is the most likely so use it here to check for a conflicting
	* mapping.
	*/
	bcopy((caddr_t)fin, (caddr_t)&fi, sizeof(fi));
	fi.fin_data[0] = sp;
	fi.fin_data[1] = fin->fin_data[1];
	nat2 = ipf_nat_outlookup(fin, IPN_TCP, nat->nat_pr[1], nat->nat_nsrcip,
	ip->ip_dst);
	if (nat2 == NULL) {
	#ifdef USE_MUTEXES
	ipf_nat_softc_t *softn = softc->ipf_nat_soft;
	#endif

	bcopy((caddr_t)fin, (caddr_t)&fi, sizeof(fi));
	bzero((char )tcp2, sizeof(tcp2));
	tcp2->th_win = htons(8192);
	tcp2->th_sport = sp;
	tcp2->th_dport = 0; /* XXX - don't specify remote port */
	fi.fin_state = NULL;
	fi.fin_nat = NULL;
	fi.fin_data[0] = ntohs(sp);
	fi.fin_data[1] = 0;
	fi.fin_dp = (char *)tcp2;
	fi.fin_fr = &ircnatfr;
	fi.fin_dlen = sizeof(*tcp2);
	fi.fin_plen = fi.fin_hlen + sizeof(*tcp2);
	swip = ip->ip_src;
	ip->ip_src = nat->nat_nsrcip;
	MUTEX_ENTER(&softn->ipf_nat_new);
	nat2 = ipf_nat_add(&fi, nat->nat_ptr, NULL,
	NAT_SLAVE\|IPN_TCP\|SI_W_DPORT, NAT_OUTBOUND);
	MUTEX_EXIT(&softn->ipf_nat_new);
	if (nat2 != NULL) {
	(void) ipf_nat_proto(&fi, nat2, 0);
	MUTEX_ENTER(&nat2->nat_lock);
	ipf_nat_update(&fi, nat2);
	MUTEX_EXIT(&nat2->nat_lock);

	if (ipf_state_add(softc, &fi, &fi.fin_state,
	SI_W_DPORT) == 0)
	ipf_state_deref(softc,
	(ipstate_t **)&fi.fin_state);
	}
	ip->ip_src = swip;
	}
	return inc;
	}


	int
	ipf_p_irc_out(arg, fin, aps, nat)
	void *arg;
	fr_info_t *fin;
	ap_session_t *aps;
	nat_t *nat;
	{
	aps = aps; /* LINT */
	return ipf_p_irc_send(fin, nat);
	}