[net-next-2.6.git] / net / ipv4 / ipvs / ip_vs_proto_udp.c

/*
 * ip_vs_proto_udp.c:	UDP load balancing support for IPVS
 *
 * Version:     $Id: ip_vs_proto_udp.c,v 1.3 2002/11/30 01:50:35 wensong Exp $
 *
 * Authors:     Wensong Zhang <wensong@linuxvirtualserver.org>
 *              Julian Anastasov <ja@ssi.bg>
 *
 *              This program 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; either version
 *              2 of the License, or (at your option) any later version.
 *
 * Changes:
 *
 */

#include <linux/in.h>
#include <linux/ip.h>
#include <linux/kernel.h>
#include <linux/netfilter_ipv4.h>
#include <linux/udp.h>

#include <net/ip_vs.h>


static struct ip_vs_conn *
udp_conn_in_get(const struct sk_buff *skb, struct ip_vs_protocol *pp,
		const struct iphdr *iph, unsigned int proto_off, int inverse)
{
	struct ip_vs_conn *cp;
	__be16 _ports[2], *pptr;

	pptr = skb_header_pointer(skb, proto_off, sizeof(_ports), _ports);
	if (pptr == NULL)
		return NULL;

	if (likely(!inverse)) {
		cp = ip_vs_conn_in_get(iph->protocol,
				       iph->saddr, pptr[0],
				       iph->daddr, pptr[1]);
	} else {
		cp = ip_vs_conn_in_get(iph->protocol,
				       iph->daddr, pptr[1],
				       iph->saddr, pptr[0]);
	}

	return cp;
}


static struct ip_vs_conn *
udp_conn_out_get(const struct sk_buff *skb, struct ip_vs_protocol *pp,
		 const struct iphdr *iph, unsigned int proto_off, int inverse)
{
	struct ip_vs_conn *cp;
	__be16 _ports[2], *pptr;

	pptr = skb_header_pointer(skb, skb->nh.iph->ihl*4,
				  sizeof(_ports), _ports);
	if (pptr == NULL)
		return NULL;

	if (likely(!inverse)) {
		cp = ip_vs_conn_out_get(iph->protocol,
					iph->saddr, pptr[0],
					iph->daddr, pptr[1]);
	} else {
		cp = ip_vs_conn_out_get(iph->protocol,
					iph->daddr, pptr[1],
					iph->saddr, pptr[0]);
	}

	return cp;
}


static int
udp_conn_schedule(struct sk_buff *skb, struct ip_vs_protocol *pp,
		  int *verdict, struct ip_vs_conn **cpp)
{
	struct ip_vs_service *svc;
	struct udphdr _udph, *uh;

	uh = skb_header_pointer(skb, skb->nh.iph->ihl*4,
				sizeof(_udph), &_udph);
	if (uh == NULL) {
		*verdict = NF_DROP;
		return 0;
	}

	if ((svc = ip_vs_service_get(skb->mark, skb->nh.iph->protocol,
				     skb->nh.iph->daddr, uh->dest))) {
		if (ip_vs_todrop()) {
			/*
			 * It seems that we are very loaded.
			 * We have to drop this packet :(
			 */
			ip_vs_service_put(svc);
			*verdict = NF_DROP;
			return 0;
		}

		/*
		 * Let the virtual server select a real server for the
		 * incoming connection, and create a connection entry.
		 */
		*cpp = ip_vs_schedule(svc, skb);
		if (!*cpp) {
			*verdict = ip_vs_leave(svc, skb, pp);
			return 0;
		}
		ip_vs_service_put(svc);
	}
	return 1;
}


static inline void
udp_fast_csum_update(struct udphdr *uhdr, __be32 oldip, __be32 newip,
		     __be16 oldport, __be16 newport)
{
	uhdr->check =
		csum_fold(ip_vs_check_diff4(oldip, newip,
				 ip_vs_check_diff2(oldport, newport,
					~csum_unfold(uhdr->check))));
	if (!uhdr->check)
		uhdr->check = CSUM_MANGLED_0;
}

static int
udp_snat_handler(struct sk_buff **pskb,
		 struct ip_vs_protocol *pp, struct ip_vs_conn *cp)
{
	struct udphdr *udph;
	unsigned int udphoff = (*pskb)->nh.iph->ihl * 4;

	/* csum_check requires unshared skb */
	if (!ip_vs_make_skb_writable(pskb, udphoff+sizeof(*udph)))
		return 0;

	if (unlikely(cp->app != NULL)) {
		/* Some checks before mangling */
		if (pp->csum_check && !pp->csum_check(*pskb, pp))
			return 0;

		/*
		 *	Call application helper if needed
		 */
		if (!ip_vs_app_pkt_out(cp, pskb))
			return 0;
	}

	udph = (void *)(*pskb)->nh.iph + udphoff;
	udph->source = cp->vport;

	/*
	 *	Adjust UDP checksums
	 */
	if (!cp->app && (udph->check != 0)) {
		/* Only port and addr are changed, do fast csum update */
		udp_fast_csum_update(udph, cp->daddr, cp->vaddr,
				     cp->dport, cp->vport);
		if ((*pskb)->ip_summed == CHECKSUM_COMPLETE)
			(*pskb)->ip_summed = CHECKSUM_NONE;
	} else {
		/* full checksum calculation */
		udph->check = 0;
		(*pskb)->csum = skb_checksum(*pskb, udphoff,
					     (*pskb)->len - udphoff, 0);
		udph->check = csum_tcpudp_magic(cp->vaddr, cp->caddr,
						(*pskb)->len - udphoff,
						cp->protocol,
						(*pskb)->csum);
		if (udph->check == 0)
			udph->check = CSUM_MANGLED_0;
		IP_VS_DBG(11, "O-pkt: %s O-csum=%d (+%zd)\n",
			  pp->name, udph->check,
			  (char*)&(udph->check) - (char*)udph);
	}
	return 1;
}


static int
udp_dnat_handler(struct sk_buff **pskb,
		 struct ip_vs_protocol *pp, struct ip_vs_conn *cp)
{
	struct udphdr *udph;
	unsigned int udphoff = (*pskb)->nh.iph->ihl * 4;

	/* csum_check requires unshared skb */
	if (!ip_vs_make_skb_writable(pskb, udphoff+sizeof(*udph)))
		return 0;

	if (unlikely(cp->app != NULL)) {
		/* Some checks before mangling */
		if (pp->csum_check && !pp->csum_check(*pskb, pp))
			return 0;

		/*
		 *	Attempt ip_vs_app call.
		 *	It will fix ip_vs_conn
		 */
		if (!ip_vs_app_pkt_in(cp, pskb))
			return 0;
	}

	udph = (void *)(*pskb)->nh.iph + udphoff;
	udph->dest = cp->dport;

	/*
	 *	Adjust UDP checksums
	 */
	if (!cp->app && (udph->check != 0)) {
		/* Only port and addr are changed, do fast csum update */
		udp_fast_csum_update(udph, cp->vaddr, cp->daddr,
				     cp->vport, cp->dport);
		if ((*pskb)->ip_summed == CHECKSUM_COMPLETE)
			(*pskb)->ip_summed = CHECKSUM_NONE;
	} else {
		/* full checksum calculation */
		udph->check = 0;
		(*pskb)->csum = skb_checksum(*pskb, udphoff,
					     (*pskb)->len - udphoff, 0);
		udph->check = csum_tcpudp_magic(cp->caddr, cp->daddr,
						(*pskb)->len - udphoff,
						cp->protocol,
						(*pskb)->csum);
		if (udph->check == 0)
			udph->check = CSUM_MANGLED_0;
		(*pskb)->ip_summed = CHECKSUM_UNNECESSARY;
	}
	return 1;
}


static int
udp_csum_check(struct sk_buff *skb, struct ip_vs_protocol *pp)
{
	struct udphdr _udph, *uh;
	unsigned int udphoff = skb->nh.iph->ihl*4;

	uh = skb_header_pointer(skb, udphoff, sizeof(_udph), &_udph);
	if (uh == NULL)
		return 0;

	if (uh->check != 0) {
		switch (skb->ip_summed) {
		case CHECKSUM_NONE:
			skb->csum = skb_checksum(skb, udphoff,
						 skb->len - udphoff, 0);
		case CHECKSUM_COMPLETE:
			if (csum_tcpudp_magic(skb->nh.iph->saddr,
					      skb->nh.iph->daddr,
					      skb->len - udphoff,
					      skb->nh.iph->protocol,
					      skb->csum)) {
				IP_VS_DBG_RL_PKT(0, pp, skb, 0,
						 "Failed checksum for");
				return 0;
			}
			break;
		default:
			/* No need to checksum. */
			break;
		}
	}
	return 1;
}


/*
 *	Note: the caller guarantees that only one of register_app,
 *	unregister_app or app_conn_bind is called each time.
 */

#define	UDP_APP_TAB_BITS	4
#define	UDP_APP_TAB_SIZE	(1 << UDP_APP_TAB_BITS)
#define	UDP_APP_TAB_MASK	(UDP_APP_TAB_SIZE - 1)

static struct list_head udp_apps[UDP_APP_TAB_SIZE];
static DEFINE_SPINLOCK(udp_app_lock);

static inline __u16 udp_app_hashkey(__be16 port)
{
	return (((__force u16)port >> UDP_APP_TAB_BITS) ^ (__force u16)port)
		& UDP_APP_TAB_MASK;
}


static int udp_register_app(struct ip_vs_app *inc)
{
	struct ip_vs_app *i;
	__u16 hash;
	__be16 port = inc->port;
	int ret = 0;

	hash = udp_app_hashkey(port);


	spin_lock_bh(&udp_app_lock);
	list_for_each_entry(i, &udp_apps[hash], p_list) {
		if (i->port == port) {
			ret = -EEXIST;
			goto out;
		}
	}
	list_add(&inc->p_list, &udp_apps[hash]);
	atomic_inc(&ip_vs_protocol_udp.appcnt);

  out:
	spin_unlock_bh(&udp_app_lock);
	return ret;
}


static void
udp_unregister_app(struct ip_vs_app *inc)
{
	spin_lock_bh(&udp_app_lock);
	atomic_dec(&ip_vs_protocol_udp.appcnt);
	list_del(&inc->p_list);
	spin_unlock_bh(&udp_app_lock);
}


static int udp_app_conn_bind(struct ip_vs_conn *cp)
{
	int hash;
	struct ip_vs_app *inc;
	int result = 0;

	/* Default binding: bind app only for NAT */
	if (IP_VS_FWD_METHOD(cp) != IP_VS_CONN_F_MASQ)
		return 0;

	/* Lookup application incarnations and bind the right one */
	hash = udp_app_hashkey(cp->vport);

	spin_lock(&udp_app_lock);
	list_for_each_entry(inc, &udp_apps[hash], p_list) {
		if (inc->port == cp->vport) {
			if (unlikely(!ip_vs_app_inc_get(inc)))
				break;
			spin_unlock(&udp_app_lock);

			IP_VS_DBG(9, "%s: Binding conn %u.%u.%u.%u:%u->"
				  "%u.%u.%u.%u:%u to app %s on port %u\n",
				  __FUNCTION__,
				  NIPQUAD(cp->caddr), ntohs(cp->cport),
				  NIPQUAD(cp->vaddr), ntohs(cp->vport),
				  inc->name, ntohs(inc->port));
			cp->app = inc;
			if (inc->init_conn)
				result = inc->init_conn(inc, cp);
			goto out;
		}
	}
	spin_unlock(&udp_app_lock);

  out:
	return result;
}


static int udp_timeouts[IP_VS_UDP_S_LAST+1] = {
	[IP_VS_UDP_S_NORMAL]		=	5*60*HZ,
	[IP_VS_UDP_S_LAST]		=	2*HZ,
};

static char * udp_state_name_table[IP_VS_UDP_S_LAST+1] = {
	[IP_VS_UDP_S_NORMAL]		=	"UDP",
	[IP_VS_UDP_S_LAST]		=	"BUG!",
};


static int
udp_set_state_timeout(struct ip_vs_protocol *pp, char *sname, int to)
{
	return ip_vs_set_state_timeout(pp->timeout_table, IP_VS_UDP_S_LAST,
				       udp_state_name_table, sname, to);
}

static const char * udp_state_name(int state)
{
	if (state >= IP_VS_UDP_S_LAST)
		return "ERR!";
	return udp_state_name_table[state] ? udp_state_name_table[state] : "?";
}

static int
udp_state_transition(struct ip_vs_conn *cp, int direction,
		     const struct sk_buff *skb,
		     struct ip_vs_protocol *pp)
{
	cp->timeout = pp->timeout_table[IP_VS_UDP_S_NORMAL];
	return 1;
}

static void udp_init(struct ip_vs_protocol *pp)
{
	IP_VS_INIT_HASH_TABLE(udp_apps);
	pp->timeout_table = udp_timeouts;
}

static void udp_exit(struct ip_vs_protocol *pp)
{
}


struct ip_vs_protocol ip_vs_protocol_udp = {
	.name =			"UDP",
	.protocol =		IPPROTO_UDP,
	.dont_defrag =		0,
	.init =			udp_init,
	.exit =			udp_exit,
	.conn_schedule =	udp_conn_schedule,
	.conn_in_get =		udp_conn_in_get,
	.conn_out_get =		udp_conn_out_get,
	.snat_handler =		udp_snat_handler,
	.dnat_handler =		udp_dnat_handler,
	.csum_check =		udp_csum_check,
	.state_transition =	udp_state_transition,
	.state_name =		udp_state_name,
	.register_app =		udp_register_app,
	.unregister_app =	udp_unregister_app,
	.app_conn_bind =	udp_app_conn_bind,
	.debug_packet =		ip_vs_tcpudp_debug_packet,
	.timeout_change =	NULL,
	.set_state_timeout =	udp_set_state_timeout,
};
Commit	Line	Data
1da177e4 LT	1	/*
	2	* ip_vs_proto_udp.c: UDP load balancing support for IPVS
	3	*
	4	* Version: $Id: ip_vs_proto_udp.c,v 1.3 2002/11/30 01:50:35 wensong Exp $
	5	*
	6	* Authors: Wensong Zhang <wensong@linuxvirtualserver.org>
	7	* Julian Anastasov <ja@ssi.bg>
	8	*
	9	* This program is free software; you can redistribute it and/or
	10	* modify it under the terms of the GNU General Public License
	11	* as published by the Free Software Foundation; either version
	12	* 2 of the License, or (at your option) any later version.
	13	*
	14	* Changes:
	15	*
	16	*/
	17
14c85021 ACM	18	#include <linux/in.h>
14c85021 ACM	19	#include <linux/ip.h>
1da177e4 LT	20	#include <linux/kernel.h>
1da177e4 LT	21	#include <linux/netfilter_ipv4.h>
14c85021	22	#include <linux/udp.h>
1da177e4 LT	23
	24	#include <net/ip_vs.h>
	25
	26
	27	static struct ip_vs_conn *
	28	udp_conn_in_get(const struct sk_buff skb, struct ip_vs_protocol pp,
	29	const struct iphdr *iph, unsigned int proto_off, int inverse)
	30	{
	31	struct ip_vs_conn *cp;
014d730d	32	__be16 _ports[2], *pptr;
1da177e4 LT	33
	34	pptr = skb_header_pointer(skb, proto_off, sizeof(_ports), _ports);
	35	if (pptr == NULL)
	36	return NULL;
	37
	38	if (likely(!inverse)) {
	39	cp = ip_vs_conn_in_get(iph->protocol,
	40	iph->saddr, pptr[0],
	41	iph->daddr, pptr[1]);
	42	} else {
	43	cp = ip_vs_conn_in_get(iph->protocol,
	44	iph->daddr, pptr[1],
	45	iph->saddr, pptr[0]);
	46	}
	47
	48	return cp;
	49	}
	50
	51
	52	static struct ip_vs_conn *
	53	udp_conn_out_get(const struct sk_buff skb, struct ip_vs_protocol pp,
	54	const struct iphdr *iph, unsigned int proto_off, int inverse)
	55	{
	56	struct ip_vs_conn *cp;
014d730d	57	__be16 _ports[2], *pptr;
1da177e4 LT	58
	59	pptr = skb_header_pointer(skb, skb->nh.iph->ihl*4,
	60	sizeof(_ports), _ports);
	61	if (pptr == NULL)
	62	return NULL;
	63
	64	if (likely(!inverse)) {
	65	cp = ip_vs_conn_out_get(iph->protocol,
	66	iph->saddr, pptr[0],
	67	iph->daddr, pptr[1]);
	68	} else {
	69	cp = ip_vs_conn_out_get(iph->protocol,
	70	iph->daddr, pptr[1],
	71	iph->saddr, pptr[0]);
	72	}
	73
	74	return cp;
	75	}
	76
	77
	78	static int
	79	udp_conn_schedule(struct sk_buff skb, struct ip_vs_protocol pp,
	80	int verdict, struct ip_vs_conn *cpp)
	81	{
	82	struct ip_vs_service *svc;
	83	struct udphdr _udph, *uh;
	84
	85	uh = skb_header_pointer(skb, skb->nh.iph->ihl*4,
	86	sizeof(_udph), &_udph);
	87	if (uh == NULL) {
	88	*verdict = NF_DROP;
	89	return 0;
	90	}
	91
82e91ffe	92	if ((svc = ip_vs_service_get(skb->mark, skb->nh.iph->protocol,
1da177e4 LT	93	skb->nh.iph->daddr, uh->dest))) {
	94	if (ip_vs_todrop()) {
	95	/*
	96	* It seems that we are very loaded.
	97	* We have to drop this packet :(
	98	*/
	99	ip_vs_service_put(svc);
	100	*verdict = NF_DROP;
	101	return 0;
	102	}
	103
	104	/*
	105	* Let the virtual server select a real server for the
	106	* incoming connection, and create a connection entry.
	107	*/
	108	*cpp = ip_vs_schedule(svc, skb);
	109	if (!*cpp) {
	110	*verdict = ip_vs_leave(svc, skb, pp);
	111	return 0;
	112	}
	113	ip_vs_service_put(svc);
	114	}
	115	return 1;
	116	}
	117
	118
	119	static inline void
014d730d AV	120	udp_fast_csum_update(struct udphdr *uhdr, __be32 oldip, __be32 newip,
014d730d AV	121	__be16 oldport, __be16 newport)
1da177e4 LT	122	{
1da177e4 LT	123	uhdr->check =
f9214b26 AV	124	csum_fold(ip_vs_check_diff4(oldip, newip,
	125	ip_vs_check_diff2(oldport, newport,
	126	~csum_unfold(uhdr->check))));
1da177e4	127	if (!uhdr->check)
f6ab0288	128	uhdr->check = CSUM_MANGLED_0;
1da177e4 LT	129	}
	130
	131	static int
	132	udp_snat_handler(struct sk_buff **pskb,
	133	struct ip_vs_protocol pp, struct ip_vs_conn cp)
	134	{
	135	struct udphdr *udph;
	136	unsigned int udphoff = (pskb)->nh.iph->ihl 4;
	137
	138	/* csum_check requires unshared skb */
	139	if (!ip_vs_make_skb_writable(pskb, udphoff+sizeof(*udph)))
	140	return 0;
	141
	142	if (unlikely(cp->app != NULL)) {
	143	/* Some checks before mangling */
	144	if (pp->csum_check && !pp->csum_check(*pskb, pp))
	145	return 0;
	146
	147	/*
	148	* Call application helper if needed
	149	*/
	150	if (!ip_vs_app_pkt_out(cp, pskb))
	151	return 0;
	152	}
	153
	154	udph = (void )(pskb)->nh.iph + udphoff;
	155	udph->source = cp->vport;
	156
	157	/*
	158	* Adjust UDP checksums
	159	*/
	160	if (!cp->app && (udph->check != 0)) {
	161	/* Only port and addr are changed, do fast csum update */
	162	udp_fast_csum_update(udph, cp->daddr, cp->vaddr,
	163	cp->dport, cp->vport);
84fa7933	164	if ((*pskb)->ip_summed == CHECKSUM_COMPLETE)
1da177e4 LT	165	(*pskb)->ip_summed = CHECKSUM_NONE;
	166	} else {
	167	/* full checksum calculation */
	168	udph->check = 0;
	169	(pskb)->csum = skb_checksum(pskb, udphoff,
	170	(*pskb)->len - udphoff, 0);
	171	udph->check = csum_tcpudp_magic(cp->vaddr, cp->caddr,
	172	(*pskb)->len - udphoff,
	173	cp->protocol,
	174	(*pskb)->csum);
	175	if (udph->check == 0)
f6ab0288	176	udph->check = CSUM_MANGLED_0;
1da177e4 LT	177	IP_VS_DBG(11, "O-pkt: %s O-csum=%d (+%zd)\n",
	178	pp->name, udph->check,
	179	(char)&(udph->check) - (char)udph);
	180	}
	181	return 1;
	182	}
	183
	184
	185	static int
	186	udp_dnat_handler(struct sk_buff **pskb,
	187	struct ip_vs_protocol pp, struct ip_vs_conn cp)
	188	{
	189	struct udphdr *udph;
	190	unsigned int udphoff = (pskb)->nh.iph->ihl 4;
	191
	192	/* csum_check requires unshared skb */
	193	if (!ip_vs_make_skb_writable(pskb, udphoff+sizeof(*udph)))
	194	return 0;
	195
	196	if (unlikely(cp->app != NULL)) {
	197	/* Some checks before mangling */
	198	if (pp->csum_check && !pp->csum_check(*pskb, pp))
	199	return 0;
	200
	201	/*
	202	* Attempt ip_vs_app call.
	203	* It will fix ip_vs_conn
	204	*/
	205	if (!ip_vs_app_pkt_in(cp, pskb))
	206	return 0;
	207	}
	208
	209	udph = (void )(pskb)->nh.iph + udphoff;
	210	udph->dest = cp->dport;
	211
	212	/*
	213	* Adjust UDP checksums
	214	*/
	215	if (!cp->app && (udph->check != 0)) {
	216	/* Only port and addr are changed, do fast csum update */
	217	udp_fast_csum_update(udph, cp->vaddr, cp->daddr,
	218	cp->vport, cp->dport);
84fa7933	219	if ((*pskb)->ip_summed == CHECKSUM_COMPLETE)
1da177e4 LT	220	(*pskb)->ip_summed = CHECKSUM_NONE;
	221	} else {
	222	/* full checksum calculation */
	223	udph->check = 0;
	224	(pskb)->csum = skb_checksum(pskb, udphoff,
	225	(*pskb)->len - udphoff, 0);
	226	udph->check = csum_tcpudp_magic(cp->caddr, cp->daddr,
	227	(*pskb)->len - udphoff,
	228	cp->protocol,
	229	(*pskb)->csum);
	230	if (udph->check == 0)
f6ab0288	231	udph->check = CSUM_MANGLED_0;
1da177e4 LT	232	(*pskb)->ip_summed = CHECKSUM_UNNECESSARY;
	233	}
	234	return 1;
	235	}
	236
	237
	238	static int
	239	udp_csum_check(struct sk_buff skb, struct ip_vs_protocol pp)
	240	{
	241	struct udphdr _udph, *uh;
	242	unsigned int udphoff = skb->nh.iph->ihl*4;
	243
	244	uh = skb_header_pointer(skb, udphoff, sizeof(_udph), &_udph);
	245	if (uh == NULL)
	246	return 0;
	247
	248	if (uh->check != 0) {
	249	switch (skb->ip_summed) {
	250	case CHECKSUM_NONE:
	251	skb->csum = skb_checksum(skb, udphoff,
	252	skb->len - udphoff, 0);
84fa7933	253	case CHECKSUM_COMPLETE:
1da177e4 LT	254	if (csum_tcpudp_magic(skb->nh.iph->saddr,
	255	skb->nh.iph->daddr,
	256	skb->len - udphoff,
	257	skb->nh.iph->protocol,
	258	skb->csum)) {
	259	IP_VS_DBG_RL_PKT(0, pp, skb, 0,
	260	"Failed checksum for");
	261	return 0;
	262	}
	263	break;
	264	default:
84fa7933	265	/* No need to checksum. */
1da177e4 LT	266	break;
	267	}
	268	}
	269	return 1;
	270	}
	271
	272
	273	/*
	274	* Note: the caller guarantees that only one of register_app,
	275	* unregister_app or app_conn_bind is called each time.
	276	*/
	277
	278	#define UDP_APP_TAB_BITS 4
	279	#define UDP_APP_TAB_SIZE (1 << UDP_APP_TAB_BITS)
	280	#define UDP_APP_TAB_MASK (UDP_APP_TAB_SIZE - 1)
	281
	282	static struct list_head udp_apps[UDP_APP_TAB_SIZE];
	283	static DEFINE_SPINLOCK(udp_app_lock);
	284
75e7ce66	285	static inline __u16 udp_app_hashkey(__be16 port)
1da177e4	286	{
75e7ce66 AV	287	return (((__force u16)port >> UDP_APP_TAB_BITS) ^ (__force u16)port)
75e7ce66 AV	288	& UDP_APP_TAB_MASK;
1da177e4 LT	289	}
	290
	291
	292	static int udp_register_app(struct ip_vs_app *inc)
	293	{
	294	struct ip_vs_app *i;
75e7ce66 AV	295	__u16 hash;
75e7ce66 AV	296	__be16 port = inc->port;
1da177e4 LT	297	int ret = 0;
	298
	299	hash = udp_app_hashkey(port);
	300
	301
	302	spin_lock_bh(&udp_app_lock);
	303	list_for_each_entry(i, &udp_apps[hash], p_list) {
	304	if (i->port == port) {
	305	ret = -EEXIST;
	306	goto out;
	307	}
	308	}
	309	list_add(&inc->p_list, &udp_apps[hash]);
	310	atomic_inc(&ip_vs_protocol_udp.appcnt);
	311
	312	out:
	313	spin_unlock_bh(&udp_app_lock);
	314	return ret;
	315	}
	316
	317
	318	static void
	319	udp_unregister_app(struct ip_vs_app *inc)
	320	{
	321	spin_lock_bh(&udp_app_lock);
	322	atomic_dec(&ip_vs_protocol_udp.appcnt);
	323	list_del(&inc->p_list);
	324	spin_unlock_bh(&udp_app_lock);
	325	}
	326
	327
	328	static int udp_app_conn_bind(struct ip_vs_conn *cp)
	329	{
	330	int hash;
	331	struct ip_vs_app *inc;
	332	int result = 0;
	333
	334	/* Default binding: bind app only for NAT */
	335	if (IP_VS_FWD_METHOD(cp) != IP_VS_CONN_F_MASQ)
	336	return 0;
	337
	338	/* Lookup application incarnations and bind the right one */
	339	hash = udp_app_hashkey(cp->vport);
	340
	341	spin_lock(&udp_app_lock);
	342	list_for_each_entry(inc, &udp_apps[hash], p_list) {
	343	if (inc->port == cp->vport) {
	344	if (unlikely(!ip_vs_app_inc_get(inc)))
	345	break;
	346	spin_unlock(&udp_app_lock);
	347
	348	IP_VS_DBG(9, "%s: Binding conn %u.%u.%u.%u:%u->"
	349	"%u.%u.%u.%u:%u to app %s on port %u\n",
	350	__FUNCTION__,
	351	NIPQUAD(cp->caddr), ntohs(cp->cport),
	352	NIPQUAD(cp->vaddr), ntohs(cp->vport),
	353	inc->name, ntohs(inc->port));
	354	cp->app = inc;
	355	if (inc->init_conn)
	356	result = inc->init_conn(inc, cp);
	357	goto out;
	358	}
	359	}
	360	spin_unlock(&udp_app_lock);
361
362	out:
363	return result;
364	}
365
366
367	static int udp_timeouts[IP_VS_UDP_S_LAST+1] = {
368	[IP_VS_UDP_S_NORMAL] = 560HZ,
369	[IP_VS_UDP_S_LAST] = 2*HZ,
370	};
371
372	static char * udp_state_name_table[IP_VS_UDP_S_LAST+1] = {
373	[IP_VS_UDP_S_NORMAL] = "UDP",
374	[IP_VS_UDP_S_LAST] = "BUG!",
375	};
376
377
378	static int
379	udp_set_state_timeout(struct ip_vs_protocol pp, char sname, int to)
380	{
381	return ip_vs_set_state_timeout(pp->timeout_table, IP_VS_UDP_S_LAST,
382	udp_state_name_table, sname, to);
383	}
384
385	static const char * udp_state_name(int state)
386	{
387	if (state >= IP_VS_UDP_S_LAST)
388	return "ERR!";
389	return udp_state_name_table[state] ? udp_state_name_table[state] : "?";
390	}
391
392	static int
393	udp_state_transition(struct ip_vs_conn *cp, int direction,
394	const struct sk_buff *skb,
395	struct ip_vs_protocol *pp)
396	{
397	cp->timeout = pp->timeout_table[IP_VS_UDP_S_NORMAL];
398	return 1;
399	}
400
401	static void udp_init(struct ip_vs_protocol *pp)
402	{
403	IP_VS_INIT_HASH_TABLE(udp_apps);
404	pp->timeout_table = udp_timeouts;
405	}
406
407	static void udp_exit(struct ip_vs_protocol *pp)
408	{
409	}
410
411
412	struct ip_vs_protocol ip_vs_protocol_udp = {
413	.name = "UDP",
414	.protocol = IPPROTO_UDP,
415	.dont_defrag = 0,
416	.init = udp_init,
417	.exit = udp_exit,
418	.conn_schedule = udp_conn_schedule,
419	.conn_in_get = udp_conn_in_get,
420	.conn_out_get = udp_conn_out_get,
421	.snat_handler = udp_snat_handler,
422	.dnat_handler = udp_dnat_handler,
423	.csum_check = udp_csum_check,
424	.state_transition = udp_state_transition,
425	.state_name = udp_state_name,
426	.register_app = udp_register_app,
427	.unregister_app = udp_unregister_app,
428	.app_conn_bind = udp_app_conn_bind,
429	.debug_packet = ip_vs_tcpudp_debug_packet,
430	.timeout_change = NULL,
431	.set_state_timeout = udp_set_state_timeout,
432	};