[net-next-2.6.git] / net / netfilter / ipvs / ip_vs_nfct.c

/*
 * ip_vs_nfct.c:	Netfilter connection tracking support for IPVS
 *
 * Portions Copyright (C) 2001-2002
 * Antefacto Ltd, 181 Parnell St, Dublin 1, Ireland.
 *
 * Portions Copyright (C) 2003-2010
 * Julian Anastasov
 *
 *
 * This code 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.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 *
 * Authors:
 * Ben North <ben@redfrontdoor.org>
 * Julian Anastasov <ja@ssi.bg>		Reorganize and sync with latest kernels
 * Hannes Eder <heder@google.com>	Extend NFCT support for FTP, ipvs match
 *
 *
 * Current status:
 *
 * - provide conntrack confirmation for new and related connections, by
 * this way we can see their proper conntrack state in all hooks
 * - support for all forwarding methods, not only NAT
 * - FTP support (NAT), ability to support other NAT apps with expectations
 * - to correctly create expectations for related NAT connections the proper
 * NF conntrack support must be already installed, eg. ip_vs_ftp requires
 * nf_conntrack_ftp ... iptables_nat for the same ports (but no iptables
 * NAT rules are needed)
 * - alter reply for NAT when forwarding packet in original direction:
 * conntrack from client in NEW or RELATED (Passive FTP DATA) state or
 * when RELATED conntrack is created from real server (Active FTP DATA)
 * - if iptables_nat is not loaded the Passive FTP will not work (the
 * PASV response can not be NAT-ed) but Active FTP should work
 *
 */

#define KMSG_COMPONENT "IPVS"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt

#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/compiler.h>
#include <linux/vmalloc.h>
#include <linux/skbuff.h>
#include <net/ip.h>
#include <linux/netfilter.h>
#include <linux/netfilter_ipv4.h>
#include <net/ip_vs.h>
#include <net/netfilter/nf_conntrack_core.h>
#include <net/netfilter/nf_conntrack_expect.h>
#include <net/netfilter/nf_conntrack_helper.h>
#include <net/netfilter/nf_conntrack_zones.h>


#define FMT_TUPLE	"%pI4:%u->%pI4:%u/%u"
#define ARG_TUPLE(T)	&(T)->src.u3.ip, ntohs((T)->src.u.all), \
			&(T)->dst.u3.ip, ntohs((T)->dst.u.all), \
			(T)->dst.protonum

#define FMT_CONN	"%pI4:%u->%pI4:%u->%pI4:%u/%u:%u"
#define ARG_CONN(C)	&((C)->caddr.ip), ntohs((C)->cport), \
			&((C)->vaddr.ip), ntohs((C)->vport), \
			&((C)->daddr.ip), ntohs((C)->dport), \
			(C)->protocol, (C)->state

void
ip_vs_update_conntrack(struct sk_buff *skb, struct ip_vs_conn *cp, int outin)
{
	enum ip_conntrack_info ctinfo;
	struct nf_conn *ct = ct = nf_ct_get(skb, &ctinfo);
	struct nf_conntrack_tuple new_tuple;

	if (ct == NULL || nf_ct_is_confirmed(ct) || nf_ct_is_untracked(ct) ||
	    nf_ct_is_dying(ct))
		return;

	/* Never alter conntrack for non-NAT conns */
	if (IP_VS_FWD_METHOD(cp) != IP_VS_CONN_F_MASQ)
		return;

	/* Alter reply only in original direction */
	if (CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL)
		return;

	/*
	 * The connection is not yet in the hashtable, so we update it.
	 * CIP->VIP will remain the same, so leave the tuple in
	 * IP_CT_DIR_ORIGINAL untouched.  When the reply comes back from the
	 * real-server we will see RIP->DIP.
	 */
	new_tuple = ct->tuplehash[IP_CT_DIR_REPLY].tuple;
	/*
	 * This will also take care of UDP and other protocols.
	 */
	if (outin) {
		new_tuple.src.u3 = cp->daddr;
		if (new_tuple.dst.protonum != IPPROTO_ICMP &&
		    new_tuple.dst.protonum != IPPROTO_ICMPV6)
			new_tuple.src.u.tcp.port = cp->dport;
	} else {
		new_tuple.dst.u3 = cp->vaddr;
		if (new_tuple.dst.protonum != IPPROTO_ICMP &&
		    new_tuple.dst.protonum != IPPROTO_ICMPV6)
			new_tuple.dst.u.tcp.port = cp->vport;
	}
	IP_VS_DBG(7, "%s: Updating conntrack ct=%p, status=0x%lX, "
		  "ctinfo=%d, old reply=" FMT_TUPLE
		  ", new reply=" FMT_TUPLE ", cp=" FMT_CONN "\n",
		  __func__, ct, ct->status, ctinfo,
		  ARG_TUPLE(&ct->tuplehash[IP_CT_DIR_REPLY].tuple),
		  ARG_TUPLE(&new_tuple), ARG_CONN(cp));
	nf_conntrack_alter_reply(ct, &new_tuple);
}

int ip_vs_confirm_conntrack(struct sk_buff *skb, struct ip_vs_conn *cp)
{
	return nf_conntrack_confirm(skb);
}

/*
 * Called from init_conntrack() as expectfn handler.
 */
static void ip_vs_nfct_expect_callback(struct nf_conn *ct,
	struct nf_conntrack_expect *exp)
{
	struct nf_conntrack_tuple *orig, new_reply;
	struct ip_vs_conn *cp;
	struct ip_vs_conn_param p;

	if (exp->tuple.src.l3num != PF_INET)
		return;

	/*
	 * We assume that no NF locks are held before this callback.
	 * ip_vs_conn_out_get and ip_vs_conn_in_get should match their
	 * expectations even if they use wildcard values, now we provide the
	 * actual values from the newly created original conntrack direction.
	 * The conntrack is confirmed when packet reaches IPVS hooks.
	 */

	/* RS->CLIENT */
	orig = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple;
	ip_vs_conn_fill_param(exp->tuple.src.l3num, orig->dst.protonum,
			      &orig->src.u3, orig->src.u.tcp.port,
			      &orig->dst.u3, orig->dst.u.tcp.port, &p);
	cp = ip_vs_conn_out_get(&p);
	if (cp) {
		/* Change reply CLIENT->RS to CLIENT->VS */
		new_reply = ct->tuplehash[IP_CT_DIR_REPLY].tuple;
		IP_VS_DBG(7, "%s: ct=%p, status=0x%lX, tuples=" FMT_TUPLE ", "
			  FMT_TUPLE ", found inout cp=" FMT_CONN "\n",
			  __func__, ct, ct->status,
			  ARG_TUPLE(orig), ARG_TUPLE(&new_reply),
			  ARG_CONN(cp));
		new_reply.dst.u3 = cp->vaddr;
		new_reply.dst.u.tcp.port = cp->vport;
		IP_VS_DBG(7, "%s: ct=%p, new tuples=" FMT_TUPLE ", " FMT_TUPLE
			  ", inout cp=" FMT_CONN "\n",
			  __func__, ct,
			  ARG_TUPLE(orig), ARG_TUPLE(&new_reply),
			  ARG_CONN(cp));
		goto alter;
	}

	/* CLIENT->VS */
	cp = ip_vs_conn_in_get(&p);
	if (cp) {
		/* Change reply VS->CLIENT to RS->CLIENT */
		new_reply = ct->tuplehash[IP_CT_DIR_REPLY].tuple;
		IP_VS_DBG(7, "%s: ct=%p, status=0x%lX, tuples=" FMT_TUPLE ", "
			  FMT_TUPLE ", found outin cp=" FMT_CONN "\n",
			  __func__, ct, ct->status,
			  ARG_TUPLE(orig), ARG_TUPLE(&new_reply),
			  ARG_CONN(cp));
		new_reply.src.u3 = cp->daddr;
		new_reply.src.u.tcp.port = cp->dport;
		IP_VS_DBG(7, "%s: ct=%p, new tuples=" FMT_TUPLE ", "
			  FMT_TUPLE ", outin cp=" FMT_CONN "\n",
			  __func__, ct,
			  ARG_TUPLE(orig), ARG_TUPLE(&new_reply),
			  ARG_CONN(cp));
		goto alter;
	}

	IP_VS_DBG(7, "%s: ct=%p, status=0x%lX, tuple=" FMT_TUPLE
		  " - unknown expect\n",
		  __func__, ct, ct->status, ARG_TUPLE(orig));
	return;

alter:
	/* Never alter conntrack for non-NAT conns */
	if (IP_VS_FWD_METHOD(cp) == IP_VS_CONN_F_MASQ)
		nf_conntrack_alter_reply(ct, &new_reply);
	ip_vs_conn_put(cp);
	return;
}

/*
 * Create NF conntrack expectation with wildcard (optional) source port.
 * Then the default callback function will alter the reply and will confirm
 * the conntrack entry when the first packet comes.
 * Use port 0 to expect connection from any port.
 */
void ip_vs_nfct_expect_related(struct sk_buff *skb, struct nf_conn *ct,
			       struct ip_vs_conn *cp, u_int8_t proto,
			       const __be16 port, int from_rs)
{
	struct nf_conntrack_expect *exp;

	if (ct == NULL || nf_ct_is_untracked(ct))
		return;

	exp = nf_ct_expect_alloc(ct);
	if (!exp)
		return;

	nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
			from_rs ? &cp->daddr : &cp->caddr,
			from_rs ? &cp->caddr : &cp->vaddr,
			proto, port ? &port : NULL,
			from_rs ? &cp->cport : &cp->vport);

	exp->expectfn = ip_vs_nfct_expect_callback;

	IP_VS_DBG(7, "%s: ct=%p, expect tuple=" FMT_TUPLE "\n",
		__func__, ct, ARG_TUPLE(&exp->tuple));
	nf_ct_expect_related(exp);
	nf_ct_expect_put(exp);
}
EXPORT_SYMBOL(ip_vs_nfct_expect_related);

/*
 * Our connection was terminated, try to drop the conntrack immediately
 */
void ip_vs_conn_drop_conntrack(struct ip_vs_conn *cp)
{
	struct nf_conntrack_tuple_hash *h;
	struct nf_conn *ct;
	struct nf_conntrack_tuple tuple;

	if (!cp->cport)
		return;

	tuple = (struct nf_conntrack_tuple) {
		.dst = { .protonum = cp->protocol, .dir = IP_CT_DIR_ORIGINAL } };
	tuple.src.u3 = cp->caddr;
	tuple.src.u.all = cp->cport;
	tuple.src.l3num = cp->af;
	tuple.dst.u3 = cp->vaddr;
	tuple.dst.u.all = cp->vport;

	IP_VS_DBG(7, "%s: dropping conntrack with tuple=" FMT_TUPLE
		" for conn " FMT_CONN "\n",
		__func__, ARG_TUPLE(&tuple), ARG_CONN(cp));

	h = nf_conntrack_find_get(&init_net, NF_CT_DEFAULT_ZONE, &tuple);
	if (h) {
		ct = nf_ct_tuplehash_to_ctrack(h);
		/* Show what happens instead of calling nf_ct_kill() */
		if (del_timer(&ct->timeout)) {
			IP_VS_DBG(7, "%s: ct=%p, deleted conntrack timer for tuple="
				FMT_TUPLE "\n",
				__func__, ct, ARG_TUPLE(&tuple));
			if (ct->timeout.function)
				ct->timeout.function(ct->timeout.data);
		} else {
			IP_VS_DBG(7, "%s: ct=%p, no conntrack timer for tuple="
				FMT_TUPLE "\n",
				__func__, ct, ARG_TUPLE(&tuple));
		}
		nf_ct_put(ct);
	} else {
		IP_VS_DBG(7, "%s: no conntrack for tuple=" FMT_TUPLE "\n",
			__func__, ARG_TUPLE(&tuple));
	}
}
Commit	Line	Data
f4bc17cd JA	1	/*
	2	* ip_vs_nfct.c: Netfilter connection tracking support for IPVS
	3	*
	4	* Portions Copyright (C) 2001-2002
	5	* Antefacto Ltd, 181 Parnell St, Dublin 1, Ireland.
	6	*
	7	* Portions Copyright (C) 2003-2010
	8	* Julian Anastasov
	9	*
	10	*
	11	* This code is free software; you can redistribute it and/or modify
	12	* it under the terms of the GNU General Public License as published by
	13	* the Free Software Foundation; either version 2 of the License, or
	14	* (at your option) any later version.
	15	*
	16	* This program is distributed in the hope that it will be useful,
	17	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	18	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	19	* GNU General Public License for more details.
	20	*
	21	* You should have received a copy of the GNU General Public License
	22	* along with this program; if not, write to the Free Software
	23	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	24	*
	25	*
	26	* Authors:
	27	* Ben North <ben@redfrontdoor.org>
	28	* Julian Anastasov <ja@ssi.bg> Reorganize and sync with latest kernels
	29	* Hannes Eder <heder@google.com> Extend NFCT support for FTP, ipvs match
	30	*
	31	*
	32	* Current status:
	33	*
	34	* - provide conntrack confirmation for new and related connections, by
	35	* this way we can see their proper conntrack state in all hooks
	36	* - support for all forwarding methods, not only NAT
	37	* - FTP support (NAT), ability to support other NAT apps with expectations
	38	* - to correctly create expectations for related NAT connections the proper
	39	* NF conntrack support must be already installed, eg. ip_vs_ftp requires
	40	* nf_conntrack_ftp ... iptables_nat for the same ports (but no iptables
	41	* NAT rules are needed)
	42	* - alter reply for NAT when forwarding packet in original direction:
	43	* conntrack from client in NEW or RELATED (Passive FTP DATA) state or
	44	* when RELATED conntrack is created from real server (Active FTP DATA)
	45	* - if iptables_nat is not loaded the Passive FTP will not work (the
	46	* PASV response can not be NAT-ed) but Active FTP should work
	47	*
	48	*/
	49
	50	#define KMSG_COMPONENT "IPVS"
	51	#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
	52
	53	#include <linux/module.h>
	54	#include <linux/types.h>
	55	#include <linux/kernel.h>
	56	#include <linux/errno.h>
	57	#include <linux/compiler.h>
	58	#include <linux/vmalloc.h>
	59	#include <linux/skbuff.h>
	60	#include <net/ip.h>
	61	#include <linux/netfilter.h>
	62	#include <linux/netfilter_ipv4.h>
	63	#include <net/ip_vs.h>
	64	#include <net/netfilter/nf_conntrack_core.h>
65	#include <net/netfilter/nf_conntrack_expect.h>
66	#include <net/netfilter/nf_conntrack_helper.h>
67	#include <net/netfilter/nf_conntrack_zones.h>
68
69
70	#define FMT_TUPLE "%pI4:%u->%pI4:%u/%u"
71	#define ARG_TUPLE(T) &(T)->src.u3.ip, ntohs((T)->src.u.all), \
72	&(T)->dst.u3.ip, ntohs((T)->dst.u.all), \
73	(T)->dst.protonum
74
75	#define FMT_CONN "%pI4:%u->%pI4:%u->%pI4:%u/%u:%u"
76	#define ARG_CONN(C) &((C)->caddr.ip), ntohs((C)->cport), \
77	&((C)->vaddr.ip), ntohs((C)->vport), \
78	&((C)->daddr.ip), ntohs((C)->dport), \
79	(C)->protocol, (C)->state
80
81	void
82	ip_vs_update_conntrack(struct sk_buff skb, struct ip_vs_conn cp, int outin)
83	{
84	enum ip_conntrack_info ctinfo;
85	struct nf_conn *ct = ct = nf_ct_get(skb, &ctinfo);
86	struct nf_conntrack_tuple new_tuple;
87
88	if (ct == NULL \|\| nf_ct_is_confirmed(ct) \|\| nf_ct_is_untracked(ct) \|\|
89	nf_ct_is_dying(ct))
90	return;
91
92	/* Never alter conntrack for non-NAT conns */
93	if (IP_VS_FWD_METHOD(cp) != IP_VS_CONN_F_MASQ)
94	return;
95
96	/* Alter reply only in original direction */
97	if (CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL)
98	return;
99
100	/*
101	* The connection is not yet in the hashtable, so we update it.
102	* CIP->VIP will remain the same, so leave the tuple in
103	* IP_CT_DIR_ORIGINAL untouched. When the reply comes back from the
104	* real-server we will see RIP->DIP.
105	*/
106	new_tuple = ct->tuplehash[IP_CT_DIR_REPLY].tuple;
107	/*
108	* This will also take care of UDP and other protocols.
109	*/
110	if (outin) {
111	new_tuple.src.u3 = cp->daddr;
112	if (new_tuple.dst.protonum != IPPROTO_ICMP &&
113	new_tuple.dst.protonum != IPPROTO_ICMPV6)
114	new_tuple.src.u.tcp.port = cp->dport;
115	} else {
116	new_tuple.dst.u3 = cp->vaddr;
117	if (new_tuple.dst.protonum != IPPROTO_ICMP &&
118	new_tuple.dst.protonum != IPPROTO_ICMPV6)
119	new_tuple.dst.u.tcp.port = cp->vport;
120	}
121	IP_VS_DBG(7, "%s: Updating conntrack ct=%p, status=0x%lX, "
122	"ctinfo=%d, old reply=" FMT_TUPLE
123	", new reply=" FMT_TUPLE ", cp=" FMT_CONN "\n",
124	__func__, ct, ct->status, ctinfo,
125	ARG_TUPLE(&ct->tuplehash[IP_CT_DIR_REPLY].tuple),
126	ARG_TUPLE(&new_tuple), ARG_CONN(cp));
127	nf_conntrack_alter_reply(ct, &new_tuple);
128	}
129
130	int ip_vs_confirm_conntrack(struct sk_buff skb, struct ip_vs_conn cp)
131	{
132	return nf_conntrack_confirm(skb);
133	}
134
135	/*
136	* Called from init_conntrack() as expectfn handler.
137	*/
138	static void ip_vs_nfct_expect_callback(struct nf_conn *ct,
139	struct nf_conntrack_expect *exp)
140	{
141	struct nf_conntrack_tuple *orig, new_reply;
142	struct ip_vs_conn *cp;
f11017ec	143	struct ip_vs_conn_param p;
f4bc17cd JA	144
	145	if (exp->tuple.src.l3num != PF_INET)
	146	return;
	147
	148	/*
	149	* We assume that no NF locks are held before this callback.
	150	* ip_vs_conn_out_get and ip_vs_conn_in_get should match their
	151	* expectations even if they use wildcard values, now we provide the
	152	* actual values from the newly created original conntrack direction.
	153	* The conntrack is confirmed when packet reaches IPVS hooks.
	154	*/
	155
	156	/* RS->CLIENT */
	157	orig = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple;
f11017ec SH	158	ip_vs_conn_fill_param(exp->tuple.src.l3num, orig->dst.protonum,
	159	&orig->src.u3, orig->src.u.tcp.port,
	160	&orig->dst.u3, orig->dst.u.tcp.port, &p);
	161	cp = ip_vs_conn_out_get(&p);
f4bc17cd JA	162	if (cp) {
	163	/* Change reply CLIENT->RS to CLIENT->VS */
	164	new_reply = ct->tuplehash[IP_CT_DIR_REPLY].tuple;
	165	IP_VS_DBG(7, "%s: ct=%p, status=0x%lX, tuples=" FMT_TUPLE ", "
	166	FMT_TUPLE ", found inout cp=" FMT_CONN "\n",
	167	__func__, ct, ct->status,
	168	ARG_TUPLE(orig), ARG_TUPLE(&new_reply),
	169	ARG_CONN(cp));
	170	new_reply.dst.u3 = cp->vaddr;
	171	new_reply.dst.u.tcp.port = cp->vport;
	172	IP_VS_DBG(7, "%s: ct=%p, new tuples=" FMT_TUPLE ", " FMT_TUPLE
	173	", inout cp=" FMT_CONN "\n",
	174	__func__, ct,
	175	ARG_TUPLE(orig), ARG_TUPLE(&new_reply),
	176	ARG_CONN(cp));
	177	goto alter;
	178	}
	179
	180	/* CLIENT->VS */
f11017ec	181	cp = ip_vs_conn_in_get(&p);
f4bc17cd JA	182	if (cp) {
	183	/* Change reply VS->CLIENT to RS->CLIENT */
	184	new_reply = ct->tuplehash[IP_CT_DIR_REPLY].tuple;
	185	IP_VS_DBG(7, "%s: ct=%p, status=0x%lX, tuples=" FMT_TUPLE ", "
	186	FMT_TUPLE ", found outin cp=" FMT_CONN "\n",
	187	__func__, ct, ct->status,
	188	ARG_TUPLE(orig), ARG_TUPLE(&new_reply),
	189	ARG_CONN(cp));
	190	new_reply.src.u3 = cp->daddr;
	191	new_reply.src.u.tcp.port = cp->dport;
	192	IP_VS_DBG(7, "%s: ct=%p, new tuples=" FMT_TUPLE ", "
	193	FMT_TUPLE ", outin cp=" FMT_CONN "\n",
	194	__func__, ct,
	195	ARG_TUPLE(orig), ARG_TUPLE(&new_reply),
	196	ARG_CONN(cp));
	197	goto alter;
	198	}
	199
	200	IP_VS_DBG(7, "%s: ct=%p, status=0x%lX, tuple=" FMT_TUPLE
	201	" - unknown expect\n",
	202	__func__, ct, ct->status, ARG_TUPLE(orig));
	203	return;
	204
	205	alter:
	206	/* Never alter conntrack for non-NAT conns */
	207	if (IP_VS_FWD_METHOD(cp) == IP_VS_CONN_F_MASQ)
	208	nf_conntrack_alter_reply(ct, &new_reply);
	209	ip_vs_conn_put(cp);
	210	return;
	211	}
	212
	213	/*
	214	* Create NF conntrack expectation with wildcard (optional) source port.
	215	* Then the default callback function will alter the reply and will confirm
	216	* the conntrack entry when the first packet comes.
	217	* Use port 0 to expect connection from any port.
	218	*/
	219	void ip_vs_nfct_expect_related(struct sk_buff skb, struct nf_conn ct,
	220	struct ip_vs_conn *cp, u_int8_t proto,
	221	const __be16 port, int from_rs)
	222	{
	223	struct nf_conntrack_expect *exp;
	224
	225	if (ct == NULL \|\| nf_ct_is_untracked(ct))
	226	return;
	227
	228	exp = nf_ct_expect_alloc(ct);
	229	if (!exp)
	230	return;
	231
	232	nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
	233	from_rs ? &cp->daddr : &cp->caddr,
	234	from_rs ? &cp->caddr : &cp->vaddr,
	235	proto, port ? &port : NULL,
	236	from_rs ? &cp->cport : &cp->vport);
	237
	238	exp->expectfn = ip_vs_nfct_expect_callback;
	239
	240	IP_VS_DBG(7, "%s: ct=%p, expect tuple=" FMT_TUPLE "\n",
	241	__func__, ct, ARG_TUPLE(&exp->tuple));
	242	nf_ct_expect_related(exp);
	243	nf_ct_expect_put(exp);
	244	}
	245	EXPORT_SYMBOL(ip_vs_nfct_expect_related);
246
247	/*
248	* Our connection was terminated, try to drop the conntrack immediately
249	*/
250	void ip_vs_conn_drop_conntrack(struct ip_vs_conn *cp)
251	{
252	struct nf_conntrack_tuple_hash *h;
253	struct nf_conn *ct;
254	struct nf_conntrack_tuple tuple;
255
256	if (!cp->cport)
257	return;
258
259	tuple = (struct nf_conntrack_tuple) {
260	.dst = { .protonum = cp->protocol, .dir = IP_CT_DIR_ORIGINAL } };
261	tuple.src.u3 = cp->caddr;
262	tuple.src.u.all = cp->cport;
263	tuple.src.l3num = cp->af;
264	tuple.dst.u3 = cp->vaddr;
265	tuple.dst.u.all = cp->vport;
266
267	IP_VS_DBG(7, "%s: dropping conntrack with tuple=" FMT_TUPLE
268	" for conn " FMT_CONN "\n",
269	__func__, ARG_TUPLE(&tuple), ARG_CONN(cp));
270
271	h = nf_conntrack_find_get(&init_net, NF_CT_DEFAULT_ZONE, &tuple);
272	if (h) {
273	ct = nf_ct_tuplehash_to_ctrack(h);
274	/* Show what happens instead of calling nf_ct_kill() */
275	if (del_timer(&ct->timeout)) {
276	IP_VS_DBG(7, "%s: ct=%p, deleted conntrack timer for tuple="
277	FMT_TUPLE "\n",
278	__func__, ct, ARG_TUPLE(&tuple));
279	if (ct->timeout.function)
280	ct->timeout.function(ct->timeout.data);
281	} else {
282	IP_VS_DBG(7, "%s: ct=%p, no conntrack timer for tuple="
283	FMT_TUPLE "\n",
284	__func__, ct, ARG_TUPLE(&tuple));
285	}
286	nf_ct_put(ct);
287	} else {
288	IP_VS_DBG(7, "%s: no conntrack for tuple=" FMT_TUPLE "\n",
289	__func__, ARG_TUPLE(&tuple));
290	}
291	}
292