Merge branch 'master' of git://1984.lsi.us.es/nf-next

Pablo says:

====================
This is the second batch of Netfilter updates for net-next. It contains the
kernel changes for the new user-space connection tracking helper
infrastructure.

More details on this infrastructure are provides here:
http://lwn.net/Articles/500196/

Still, I plan to provide some official documentation through the
conntrack-tools user manual on how to setup user-space utilities for this.
So far, it provides two helper in user-space, one for NFSv3 and another for
Oracle/SQLnet/TNS. Yet in my TODO list.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/netfilter.h

@@ -393,6 +393,18 @@ nf_nat_decode_session(struct sk_buff *skb, struct flowi *fl, u_int8_t family)
 extern void (*ip_ct_attach)(struct sk_buff *, struct sk_buff *) __rcu;
 extern void nf_ct_attach(struct sk_buff *, struct sk_buff *);
 extern void (*nf_ct_destroy)(struct nf_conntrack *) __rcu;
+
+struct nf_conn;
+struct nlattr;
+
+struct nfq_ct_hook {
+	size_t (*build_size)(const struct nf_conn *ct);
+	int (*build)(struct sk_buff *skb, struct nf_conn *ct);
+	int (*parse)(const struct nlattr *attr, struct nf_conn *ct);
+	void (*seq_adjust)(struct sk_buff *skb, struct nf_conn *ct,
+			   u32 ctinfo, int off);
+};
+extern struct nfq_ct_hook *nfq_ct_hook;
 #else
 static inline void nf_ct_attach(struct sk_buff *new, struct sk_buff *skb) {}
 #endif

include/linux/netfilter/Kbuild

@@ -10,6 +10,7 @@ header-y += nfnetlink.h
 header-y += nfnetlink_acct.h
 header-y += nfnetlink_compat.h
 header-y += nfnetlink_conntrack.h
+header-y += nfnetlink_cthelper.h
 header-y += nfnetlink_cttimeout.h
 header-y += nfnetlink_log.h
 header-y += nfnetlink_queue.h

include/linux/netfilter/nf_conntrack_sip.h

@@ -2,6 +2,8 @@
 #define __NF_CONNTRACK_SIP_H__
 #ifdef __KERNEL__
 
+#include <net/netfilter/nf_conntrack_expect.h>
+
 #define SIP_PORT	5060
 #define SIP_TIMEOUT	3600
 

include/linux/netfilter/nfnetlink.h

@@ -50,7 +50,8 @@ struct nfgenmsg {
 #define NFNL_SUBSYS_IPSET		6
 #define NFNL_SUBSYS_ACCT		7
 #define NFNL_SUBSYS_CTNETLINK_TIMEOUT	8
-#define NFNL_SUBSYS_COUNT		9
+#define NFNL_SUBSYS_CTHELPER		9
+#define NFNL_SUBSYS_COUNT		10
 
 #ifdef __KERNEL__
 

include/linux/netfilter/nfnetlink_conntrack.h

@@ -191,6 +191,7 @@ enum ctattr_expect_nat {
 enum ctattr_help {
 	CTA_HELP_UNSPEC,
 	CTA_HELP_NAME,
+	CTA_HELP_INFO,
 	__CTA_HELP_MAX
 };
 #define CTA_HELP_MAX (__CTA_HELP_MAX - 1)

include/linux/netfilter/nfnetlink_cthelper.h

+#ifndef _NFNL_CTHELPER_H_
+#define _NFNL_CTHELPER_H_
+
+#define NFCT_HELPER_STATUS_DISABLED	0
+#define NFCT_HELPER_STATUS_ENABLED	1
+
+enum nfnl_acct_msg_types {
+	NFNL_MSG_CTHELPER_NEW,
+	NFNL_MSG_CTHELPER_GET,
+	NFNL_MSG_CTHELPER_DEL,
+	NFNL_MSG_CTHELPER_MAX
+};
+
+enum nfnl_cthelper_type {
+	NFCTH_UNSPEC,
+	NFCTH_NAME,
+	NFCTH_TUPLE,
+	NFCTH_QUEUE_NUM,
+	NFCTH_POLICY,
+	NFCTH_PRIV_DATA_LEN,
+	NFCTH_STATUS,
+	__NFCTH_MAX
+};
+#define NFCTH_MAX (__NFCTH_MAX - 1)
+
+enum nfnl_cthelper_policy_type {
+	NFCTH_POLICY_SET_UNSPEC,
+	NFCTH_POLICY_SET_NUM,
+	NFCTH_POLICY_SET,
+	NFCTH_POLICY_SET1	= NFCTH_POLICY_SET,
+	NFCTH_POLICY_SET2,
+	NFCTH_POLICY_SET3,
+	NFCTH_POLICY_SET4,
+	__NFCTH_POLICY_SET_MAX
+};
+#define NFCTH_POLICY_SET_MAX (__NFCTH_POLICY_SET_MAX - 1)
+
+enum nfnl_cthelper_pol_type {
+	NFCTH_POLICY_UNSPEC,
+	NFCTH_POLICY_NAME,
+	NFCTH_POLICY_EXPECT_MAX,
+	NFCTH_POLICY_EXPECT_TIMEOUT,
+	__NFCTH_POLICY_MAX
+};
+#define NFCTH_POLICY_MAX (__NFCTH_POLICY_MAX - 1)
+
+enum nfnl_cthelper_tuple_type {
+	NFCTH_TUPLE_UNSPEC,
+	NFCTH_TUPLE_L3PROTONUM,
+	NFCTH_TUPLE_L4PROTONUM,
+	__NFCTH_TUPLE_MAX,
+};
+#define NFCTH_TUPLE_MAX (__NFCTH_TUPLE_MAX - 1)
+
+#endif /* _NFNL_CTHELPER_H */

include/linux/netfilter/nfnetlink_queue.h

@@ -42,6 +42,8 @@ enum nfqnl_attr_type {
 	NFQA_IFINDEX_PHYSOUTDEV,	/* __u32 ifindex */
 	NFQA_HWADDR,			/* nfqnl_msg_packet_hw */
 	NFQA_PAYLOAD,			/* opaque data payload */
+	NFQA_CT,			/* nf_conntrack_netlink.h */
+	NFQA_CT_INFO,			/* enum ip_conntrack_info */
 
 	__NFQA_MAX
 };
@@ -92,5 +94,6 @@ enum nfqnl_attr_config {
 
 /* Flags for NFQA_CFG_FLAGS */
 #define NFQA_CFG_F_FAIL_OPEN			(1 << 0)
+#define NFQA_CFG_F_CONNTRACK			(1 << 1)
 
 #endif /* _NFNETLINK_QUEUE_H */

include/linux/netfilter_ipv4.h

@@ -66,6 +66,7 @@ enum nf_ip_hook_priorities {
 	NF_IP_PRI_SECURITY = 50,
 	NF_IP_PRI_NAT_SRC = 100,
 	NF_IP_PRI_SELINUX_LAST = 225,
+	NF_IP_PRI_CONNTRACK_HELPER = 300,
 	NF_IP_PRI_CONNTRACK_CONFIRM = INT_MAX,
 	NF_IP_PRI_LAST = INT_MAX,
 };

include/linux/netfilter_ipv6.h

@@ -71,6 +71,7 @@ enum nf_ip6_hook_priorities {
 	NF_IP6_PRI_SECURITY = 50,
 	NF_IP6_PRI_NAT_SRC = 100,
 	NF_IP6_PRI_SELINUX_LAST = 225,
+	NF_IP6_PRI_CONNTRACK_HELPER = 300,
 	NF_IP6_PRI_LAST = INT_MAX,
 };
 

include/net/netfilter/nf_conntrack.h

@@ -39,36 +39,6 @@ union nf_conntrack_expect_proto {
 	/* insert expect proto private data here */
 };
 
-/* Add protocol helper include file here */
-#include <linux/netfilter/nf_conntrack_ftp.h>
-#include <linux/netfilter/nf_conntrack_pptp.h>
-#include <linux/netfilter/nf_conntrack_h323.h>
-#include <linux/netfilter/nf_conntrack_sane.h>
-#include <linux/netfilter/nf_conntrack_sip.h>
-
-/* per conntrack: application helper private data */
-union nf_conntrack_help {
-	/* insert conntrack helper private data (master) here */
-#if defined(CONFIG_NF_CONNTRACK_FTP) || defined(CONFIG_NF_CONNTRACK_FTP_MODULE)
-	struct nf_ct_ftp_master ct_ftp_info;
-#endif
-#if defined(CONFIG_NF_CONNTRACK_PPTP) || \
-    defined(CONFIG_NF_CONNTRACK_PPTP_MODULE)
-	struct nf_ct_pptp_master ct_pptp_info;
-#endif
-#if defined(CONFIG_NF_CONNTRACK_H323) || \
-    defined(CONFIG_NF_CONNTRACK_H323_MODULE)
-	struct nf_ct_h323_master ct_h323_info;
-#endif
-#if defined(CONFIG_NF_CONNTRACK_SANE) || \
-    defined(CONFIG_NF_CONNTRACK_SANE_MODULE)
-	struct nf_ct_sane_master ct_sane_info;
-#endif
-#if defined(CONFIG_NF_CONNTRACK_SIP) || defined(CONFIG_NF_CONNTRACK_SIP_MODULE)
-	struct nf_ct_sip_master ct_sip_info;
-#endif
-};
-
 #include <linux/types.h>
 #include <linux/skbuff.h>
 #include <linux/timer.h>
@@ -89,12 +59,13 @@ struct nf_conn_help {
 	/* Helper. if any */
 	struct nf_conntrack_helper __rcu *helper;
 
-	union nf_conntrack_help help;
-
 	struct hlist_head expectations;
 
 	/* Current number of expected connections */
 	u8 expecting[NF_CT_MAX_EXPECT_CLASSES];
+
+	/* private helper information. */
+	char data[];
 };
 
 #include <net/netfilter/ipv4/nf_conntrack_ipv4.h>

include/net/netfilter/nf_conntrack_expect.h

@@ -59,10 +59,12 @@ static inline struct net *nf_ct_exp_net(struct nf_conntrack_expect *exp)
 	return nf_ct_net(exp->master);
 }
 
+#define NF_CT_EXP_POLICY_NAME_LEN	16
+
 struct nf_conntrack_expect_policy {
 	unsigned int	max_expected;
 	unsigned int	timeout;
-	const char	*name;
+	char		name[NF_CT_EXP_POLICY_NAME_LEN];
 };
 
 #define NF_CT_EXPECT_CLASS_DEFAULT	0

include/net/netfilter/nf_conntrack_extend.h

@@ -80,10 +80,13 @@ static inline void nf_ct_ext_free(struct nf_conn *ct)
 }
 
 /* Add this type, returns pointer to data or NULL. */
-void *
-__nf_ct_ext_add(struct nf_conn *ct, enum nf_ct_ext_id id, gfp_t gfp);
+void *__nf_ct_ext_add_length(struct nf_conn *ct, enum nf_ct_ext_id id,
+			     size_t var_alloc_len, gfp_t gfp);
+
 #define nf_ct_ext_add(ct, id, gfp) \
-	((id##_TYPE *)__nf_ct_ext_add((ct), (id), (gfp)))
+	((id##_TYPE *)__nf_ct_ext_add_length((ct), (id), 0, (gfp)))
+#define nf_ct_ext_add_length(ct, id, len, gfp) \
+	((id##_TYPE *)__nf_ct_ext_add_length((ct), (id), (len), (gfp)))
 
 #define NF_CT_EXT_F_PREALLOC	0x0001
 

include/net/netfilter/nf_conntrack_helper.h

@@ -11,18 +11,27 @@
 #define _NF_CONNTRACK_HELPER_H
 #include <net/netfilter/nf_conntrack.h>
 #include <net/netfilter/nf_conntrack_extend.h>
+#include <net/netfilter/nf_conntrack_expect.h>
 
 struct module;
 
+enum nf_ct_helper_flags {
+	NF_CT_HELPER_F_USERSPACE	= (1 << 0),
+	NF_CT_HELPER_F_CONFIGURED	= (1 << 1),
+};
+
 #define NF_CT_HELPER_NAME_LEN	16
 
 struct nf_conntrack_helper {
 	struct hlist_node hnode;	/* Internal use. */
 
-	const char *name;		/* name of the module */
+	char name[NF_CT_HELPER_NAME_LEN]; /* name of the module */
 	struct module *me;		/* pointer to self */
 	const struct nf_conntrack_expect_policy *expect_policy;
 
+	/* length of internal data, ie. sizeof(struct nf_ct_*_master) */
+	size_t data_len;
+
 	/* Tuple of things we will help (compared against server response) */
 	struct nf_conntrack_tuple tuple;
 
@@ -35,8 +44,12 @@ struct nf_conntrack_helper {
 
 	void (*destroy)(struct nf_conn *ct);
 
+	int (*from_nlattr)(struct nlattr *attr, struct nf_conn *ct);
 	int (*to_nlattr)(struct sk_buff *skb, const struct nf_conn *ct);
 	unsigned int expect_class_max;
+
+	unsigned int flags;
+	unsigned int queue_num;		/* For user-space helpers. */
 };
 
 extern struct nf_conntrack_helper *
@@ -48,7 +61,7 @@ nf_conntrack_helper_try_module_get(const char *name, u16 l3num, u8 protonum);
 extern int nf_conntrack_helper_register(struct nf_conntrack_helper *);
 extern void nf_conntrack_helper_unregister(struct nf_conntrack_helper *);
 
-extern struct nf_conn_help *nf_ct_helper_ext_add(struct nf_conn *ct, gfp_t gfp);
+extern struct nf_conn_help *nf_ct_helper_ext_add(struct nf_conn *ct, struct nf_conntrack_helper *helper, gfp_t gfp);
 
 extern int __nf_ct_try_assign_helper(struct nf_conn *ct, struct nf_conn *tmpl,
 				     gfp_t flags);
@@ -60,6 +73,15 @@ static inline struct nf_conn_help *nfct_help(const struct nf_conn *ct)
 	return nf_ct_ext_find(ct, NF_CT_EXT_HELPER);
 }
 
+static inline void *nfct_help_data(const struct nf_conn *ct)
+{
+	struct nf_conn_help *help;
+
+	help = nf_ct_ext_find(ct, NF_CT_EXT_HELPER);
+
+	return (void *)help->data;
+}
+
 extern int nf_conntrack_helper_init(struct net *net);
 extern void nf_conntrack_helper_fini(struct net *net);
 
@@ -82,4 +104,7 @@ nf_ct_helper_expectfn_find_by_name(const char *name);
 struct nf_ct_helper_expectfn *
 nf_ct_helper_expectfn_find_by_symbol(const void *symbol);
 
+extern struct hlist_head *nf_ct_helper_hash;
+extern unsigned int nf_ct_helper_hsize;
+
 #endif /*_NF_CONNTRACK_HELPER_H*/

include/net/netfilter/nf_nat_helper.h

@@ -54,4 +54,8 @@ extern void nf_nat_follow_master(struct nf_conn *ct,
 extern s16 nf_nat_get_offset(const struct nf_conn *ct,
 			     enum ip_conntrack_dir dir,
 			     u32 seq);
+
+extern void nf_nat_tcp_seq_adjust(struct sk_buff *skb, struct nf_conn *ct,
+				  u32 dir, int off);
+
 #endif

net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c

@@ -95,7 +95,7 @@ static int ipv4_get_l4proto(const struct sk_buff *skb, unsigned int nhoff,
 	return NF_ACCEPT;
 }
 
-static unsigned int ipv4_confirm(unsigned int hooknum,
+static unsigned int ipv4_helper(unsigned int hooknum,
 				struct sk_buff *skb,
 				const struct net_device *in,
 				const struct net_device *out,
@@ -110,24 +110,38 @@ static unsigned int ipv4_confirm(unsigned int hooknum,
 	/* This is where we call the helper: as the packet goes out. */
 	ct = nf_ct_get(skb, &ctinfo);
 	if (!ct || ctinfo == IP_CT_RELATED_REPLY)
-		goto out;
+		return NF_ACCEPT;
 
 	help = nfct_help(ct);
 	if (!help)
-		goto out;
+		return NF_ACCEPT;
 
 	/* rcu_read_lock()ed by nf_hook_slow */
 	helper = rcu_dereference(help->helper);
 	if (!helper)
-		goto out;
+		return NF_ACCEPT;
 
 	ret = helper->help(skb, skb_network_offset(skb) + ip_hdrlen(skb),
 			   ct, ctinfo);
-	if (ret != NF_ACCEPT) {
+	if (ret != NF_ACCEPT && (ret & NF_VERDICT_MASK) != NF_QUEUE) {
 		nf_log_packet(NFPROTO_IPV4, hooknum, skb, in, out, NULL,
 			      "nf_ct_%s: dropping packet", helper->name);
-		return ret;
 	}
+	return ret;
+}
+
+static unsigned int ipv4_confirm(unsigned int hooknum,
+				 struct sk_buff *skb,
+				 const struct net_device *in,
+				 const struct net_device *out,
+				 int (*okfn)(struct sk_buff *))
+{
+	struct nf_conn *ct;
+	enum ip_conntrack_info ctinfo;
+
+	ct = nf_ct_get(skb, &ctinfo);
+	if (!ct || ctinfo == IP_CT_RELATED_REPLY)
+		goto out;
 
 	/* adjust seqs for loopback traffic only in outgoing direction */
 	if (test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) &&
@@ -184,6 +198,13 @@ static struct nf_hook_ops ipv4_conntrack_ops[] __read_mostly = {
 		.hooknum	= NF_INET_LOCAL_OUT,
 		.priority	= NF_IP_PRI_CONNTRACK,
 	},
+	{
+		.hook		= ipv4_helper,
+		.owner		= THIS_MODULE,
+		.pf		= NFPROTO_IPV4,
+		.hooknum	= NF_INET_POST_ROUTING,
+		.priority	= NF_IP_PRI_CONNTRACK_HELPER,
+	},
 	{
 		.hook		= ipv4_confirm,
 		.owner		= THIS_MODULE,
@@ -191,6 +212,13 @@ static struct nf_hook_ops ipv4_conntrack_ops[] __read_mostly = {
 		.hooknum	= NF_INET_POST_ROUTING,
 		.priority	= NF_IP_PRI_CONNTRACK_CONFIRM,
 	},
+	{
+		.hook		= ipv4_helper,
+		.owner		= THIS_MODULE,
+		.pf		= NFPROTO_IPV4,
+		.hooknum	= NF_INET_LOCAL_IN,
+		.priority	= NF_IP_PRI_CONNTRACK_HELPER,
+	},
 	{
 		.hook		= ipv4_confirm,
 		.owner		= THIS_MODULE,

net/ipv4/netfilter/nf_nat_amanda.c

@@ -13,10 +13,10 @@
 #include <linux/skbuff.h>
 #include <linux/udp.h>
 
-#include <net/netfilter/nf_nat_helper.h>
-#include <net/netfilter/nf_nat_rule.h>
 #include <net/netfilter/nf_conntrack_helper.h>
 #include <net/netfilter/nf_conntrack_expect.h>
+#include <net/netfilter/nf_nat_helper.h>
+#include <net/netfilter/nf_nat_rule.h>
 #include <linux/netfilter/nf_conntrack_amanda.h>
 
 MODULE_AUTHOR("Brian J. Murrell <netfilter@interlinx.bc.ca>");

net/ipv4/netfilter/nf_nat_h323.c

@@ -95,7 +95,7 @@ static int set_sig_addr(struct sk_buff *skb, struct nf_conn *ct,
 			unsigned char **data,
 			TransportAddress *taddr, int count)
 {
-	const struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
+	const struct nf_ct_h323_master *info = nfct_help_data(ct);
 	int dir = CTINFO2DIR(ctinfo);
 	int i;
 	__be16 port;
@@ -178,7 +178,7 @@ static int nat_rtp_rtcp(struct sk_buff *skb, struct nf_conn *ct,
 			struct nf_conntrack_expect *rtp_exp,
 			struct nf_conntrack_expect *rtcp_exp)
 {
-	struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
+	struct nf_ct_h323_master *info = nfct_help_data(ct);
 	int dir = CTINFO2DIR(ctinfo);
 	int i;
 	u_int16_t nated_port;
@@ -330,7 +330,7 @@ static int nat_h245(struct sk_buff *skb, struct nf_conn *ct,
 		    TransportAddress *taddr, __be16 port,
 		    struct nf_conntrack_expect *exp)
 {
-	struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
+	struct nf_ct_h323_master *info = nfct_help_data(ct);
 	int dir = CTINFO2DIR(ctinfo);
 	u_int16_t nated_port = ntohs(port);
 
@@ -419,7 +419,7 @@ static int nat_q931(struct sk_buff *skb, struct nf_conn *ct,
 		    unsigned char **data, TransportAddress *taddr, int idx,
 		    __be16 port, struct nf_conntrack_expect *exp)
 {
-	struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
+	struct nf_ct_h323_master *info = nfct_help_data(ct);
 	int dir = CTINFO2DIR(ctinfo);
 	u_int16_t nated_port = ntohs(port);
 	union nf_inet_addr addr;

net/ipv4/netfilter/nf_nat_helper.c

@@ -153,6 +153,19 @@ void nf_nat_set_seq_adjust(struct nf_conn *ct, enum ip_conntrack_info ctinfo,
 }
 EXPORT_SYMBOL_GPL(nf_nat_set_seq_adjust);
 
+void nf_nat_tcp_seq_adjust(struct sk_buff *skb, struct nf_conn *ct,
+			   u32 ctinfo, int off)
+{
+	const struct tcphdr *th;
+
+	if (nf_ct_protonum(ct) != IPPROTO_TCP)
+		return;
+
+	th = (struct tcphdr *)(skb_network_header(skb)+ ip_hdrlen(skb));
+	nf_nat_set_seq_adjust(ct, ctinfo, th->seq, off);
+}
+EXPORT_SYMBOL_GPL(nf_nat_tcp_seq_adjust);
+
 static void nf_nat_csum(struct sk_buff *skb, const struct iphdr *iph, void *data,
 			int datalen, __sum16 *check, int oldlen)
 {

net/ipv4/netfilter/nf_nat_pptp.c

@@ -49,7 +49,7 @@ static void pptp_nat_expected(struct nf_conn *ct,
 	const struct nf_nat_pptp *nat_pptp_info;
 	struct nf_nat_ipv4_range range;
 
-	ct_pptp_info = &nfct_help(master)->help.ct_pptp_info;
+	ct_pptp_info = nfct_help_data(master);
 	nat_pptp_info = &nfct_nat(master)->help.nat_pptp_info;
 
 	/* And here goes the grand finale of corrosion... */
@@ -123,7 +123,7 @@ pptp_outbound_pkt(struct sk_buff *skb,
 	__be16 new_callid;
 	unsigned int cid_off;
 
-	ct_pptp_info  = &nfct_help(ct)->help.ct_pptp_info;
+	ct_pptp_info = nfct_help_data(ct);
 	nat_pptp_info = &nfct_nat(ct)->help.nat_pptp_info;
 
 	new_callid = ct_pptp_info->pns_call_id;
@@ -192,7 +192,7 @@ pptp_exp_gre(struct nf_conntrack_expect *expect_orig,
 	struct nf_ct_pptp_master *ct_pptp_info;
 	struct nf_nat_pptp *nat_pptp_info;
 
-	ct_pptp_info  = &nfct_help(ct)->help.ct_pptp_info;
+	ct_pptp_info = nfct_help_data(ct);
 	nat_pptp_info = &nfct_nat(ct)->help.nat_pptp_info;
 
 	/* save original PAC call ID in nat_info */

net/ipv4/netfilter/nf_nat_tftp.c

@@ -8,10 +8,10 @@
 #include <linux/module.h>
 #include <linux/udp.h>
 
-#include <net/netfilter/nf_nat_helper.h>
-#include <net/netfilter/nf_nat_rule.h>
 #include <net/netfilter/nf_conntrack_helper.h>
 #include <net/netfilter/nf_conntrack_expect.h>
+#include <net/netfilter/nf_nat_helper.h>
+#include <net/netfilter/nf_nat_rule.h>
 #include <linux/netfilter/nf_conntrack_tftp.h>
 
 MODULE_AUTHOR("Magnus Boden <mb@ozaba.mine.nu>");

net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c

@@ -143,7 +143,7 @@ static int ipv6_get_l4proto(const struct sk_buff *skb, unsigned int nhoff,
 	return NF_ACCEPT;
 }
 
-static unsigned int ipv6_confirm(unsigned int hooknum,
+static unsigned int ipv6_helper(unsigned int hooknum,
 				struct sk_buff *skb,
 				const struct net_device *in,
 				const struct net_device *out,
@@ -161,15 +161,15 @@ static unsigned int ipv6_confirm(unsigned int hooknum,
 	/* This is where we call the helper: as the packet goes out. */
 	ct = nf_ct_get(skb, &ctinfo);
 	if (!ct || ctinfo == IP_CT_RELATED_REPLY)
-		goto out;
+		return NF_ACCEPT;
 
 	help = nfct_help(ct);
 	if (!help)
-		goto out;
+		return NF_ACCEPT;
 	/* rcu_read_lock()ed by nf_hook_slow */
 	helper = rcu_dereference(help->helper);
 	if (!helper)
-		goto out;
+		return NF_ACCEPT;
 
 	protoff = nf_ct_ipv6_skip_exthdr(skb, extoff, &pnum,
 					 skb->len - extoff);
@@ -179,12 +179,19 @@ static unsigned int ipv6_confirm(unsigned int hooknum,
 	}
 
 	ret = helper->help(skb, protoff, ct, ctinfo);
-	if (ret != NF_ACCEPT) {
+	if (ret != NF_ACCEPT && (ret & NF_VERDICT_MASK) != NF_QUEUE) {
 		nf_log_packet(NFPROTO_IPV6, hooknum, skb, in, out, NULL,
 			      "nf_ct_%s: dropping packet", helper->name);
-		return ret;
 	}
-out:
+	return ret;
+}
+
+static unsigned int ipv6_confirm(unsigned int hooknum,
+				 struct sk_buff *skb,
+				 const struct net_device *in,
+				 const struct net_device *out,
+				 int (*okfn)(struct sk_buff *))
+{
 	/* We've seen it coming out the other side: confirm it */
 	return nf_conntrack_confirm(skb);
 }
@@ -253,6 +260,13 @@ static struct nf_hook_ops ipv6_conntrack_ops[] __read_mostly = {
 		.hooknum	= NF_INET_LOCAL_OUT,
 		.priority	= NF_IP6_PRI_CONNTRACK,
 	},
+	{
+		.hook		= ipv6_helper,
+		.owner		= THIS_MODULE,
+		.pf		= NFPROTO_IPV6,
+		.hooknum	= NF_INET_POST_ROUTING,
+		.priority	= NF_IP6_PRI_CONNTRACK_HELPER,
+	},
 	{
 		.hook		= ipv6_confirm,
 		.owner		= THIS_MODULE,
@@ -260,6 +274,13 @@ static struct nf_hook_ops ipv6_conntrack_ops[] __read_mostly = {
 		.hooknum	= NF_INET_POST_ROUTING,
 		.priority	= NF_IP6_PRI_LAST,
 	},
+	{
+		.hook		= ipv6_helper,
+		.owner		= THIS_MODULE,
+		.pf		= NFPROTO_IPV6,
+		.hooknum	= NF_INET_LOCAL_IN,
+		.priority	= NF_IP6_PRI_CONNTRACK_HELPER,
+	},
 	{
 		.hook		= ipv6_confirm,
 		.owner		= THIS_MODULE,

net/netfilter/Kconfig

@@ -12,6 +12,14 @@ tristate "Netfilter NFACCT over NFNETLINK interface"
 	  If this option is enabled, the kernel will include support
 	  for extended accounting via NFNETLINK.
 
+config NETFILTER_NETLINK_CTHELPER
+tristate "Netfilter CTHELPER over NFNETLINK interface"
+	depends on NETFILTER_ADVANCED
+	select NETFILTER_NETLINK
+	help
+	  If this option is enabled, the kernel will include support
+	  for user-space connection tracking helpers via NFNETLINK.
+
 config NETFILTER_NETLINK_QUEUE
 	tristate "Netfilter NFQUEUE over NFNETLINK interface"
 	depends on NETFILTER_ADVANCED

net/netfilter/Makefile

@@ -9,6 +9,7 @@ obj-$(CONFIG_NETFILTER) = netfilter.o
 
 obj-$(CONFIG_NETFILTER_NETLINK) += nfnetlink.o
 obj-$(CONFIG_NETFILTER_NETLINK_ACCT) += nfnetlink_acct.o
+obj-$(CONFIG_NETFILTER_NETLINK_CTHELPER) += nfnetlink_cthelper.o
 obj-$(CONFIG_NETFILTER_NETLINK_QUEUE) += nfnetlink_queue.o
 obj-$(CONFIG_NETFILTER_NETLINK_LOG) += nfnetlink_log.o
 

net/netfilter/core.c

@@ -264,6 +264,10 @@ void nf_conntrack_destroy(struct nf_conntrack *nfct)
 	rcu_read_unlock();
 }
 EXPORT_SYMBOL(nf_conntrack_destroy);
+
+struct nfq_ct_hook *nfq_ct_hook;
+EXPORT_SYMBOL_GPL(nfq_ct_hook);
+
 #endif /* CONFIG_NF_CONNTRACK */
 
 #ifdef CONFIG_PROC_FS

net/netfilter/nf_conntrack_core.c

@@ -819,7 +819,8 @@ init_conntrack(struct net *net, struct nf_conn *tmpl,
 		__set_bit(IPS_EXPECTED_BIT, &ct->status);
 		ct->master = exp->master;
 		if (exp->helper) {
-			help = nf_ct_helper_ext_add(ct, GFP_ATOMIC);
+			help = nf_ct_helper_ext_add(ct, exp->helper,
+						    GFP_ATOMIC);
 			if (help)
 				rcu_assign_pointer(help->helper, exp->helper);
 		}

net/netfilter/nf_conntrack_extend.c

@@ -44,7 +44,8 @@ void __nf_ct_ext_destroy(struct nf_conn *ct)
 EXPORT_SYMBOL(__nf_ct_ext_destroy);
 
 static void *
-nf_ct_ext_create(struct nf_ct_ext **ext, enum nf_ct_ext_id id, gfp_t gfp)
+nf_ct_ext_create(struct nf_ct_ext **ext, enum nf_ct_ext_id id,
+		 size_t var_alloc_len, gfp_t gfp)
 {
 	unsigned int off, len;
 	struct nf_ct_ext_type *t;
@@ -54,8 +55,8 @@ nf_ct_ext_create(struct nf_ct_ext **ext, enum nf_ct_ext_id id, gfp_t gfp)
 	t = rcu_dereference(nf_ct_ext_types[id]);
 	BUG_ON(t == NULL);
 	off = ALIGN(sizeof(struct nf_ct_ext), t->align);
-	len = off + t->len;
-	alloc_size = t->alloc_size;
+	len = off + t->len + var_alloc_len;
+	alloc_size = t->alloc_size + var_alloc_len;
 	rcu_read_unlock();
 
 	*ext = kzalloc(alloc_size, gfp);
@@ -68,7 +69,8 @@ nf_ct_ext_create(struct nf_ct_ext **ext, enum nf_ct_ext_id id, gfp_t gfp)
 	return (void *)(*ext) + off;
 }
 
-void *__nf_ct_ext_add(struct nf_conn *ct, enum nf_ct_ext_id id, gfp_t gfp)
+void *__nf_ct_ext_add_length(struct nf_conn *ct, enum nf_ct_ext_id id,
+			     size_t var_alloc_len, gfp_t gfp)
 {
 	struct nf_ct_ext *old, *new;
 	int i, newlen, newoff;
@@ -79,7 +81,7 @@ void *__nf_ct_ext_add(struct nf_conn *ct, enum nf_ct_ext_id id, gfp_t gfp)
 
 	old = ct->ext;
 	if (!old)
-		return nf_ct_ext_create(&ct->ext, id, gfp);
+		return nf_ct_ext_create(&ct->ext, id, var_alloc_len, gfp);
 
 	if (__nf_ct_ext_exist(old, id))
 		return NULL;
@@ -89,7 +91,7 @@ void *__nf_ct_ext_add(struct nf_conn *ct, enum nf_ct_ext_id id, gfp_t gfp)
 	BUG_ON(t == NULL);
 
 	newoff = ALIGN(old->len, t->align);
-	newlen = newoff + t->len;
+	newlen = newoff + t->len + var_alloc_len;
 	rcu_read_unlock();
 
 	new = __krealloc(old, newlen, gfp);
@@ -117,7 +119,7 @@ void *__nf_ct_ext_add(struct nf_conn *ct, enum nf_ct_ext_id id, gfp_t gfp)
 	memset((void *)new + newoff, 0, newlen - newoff);
 	return (void *)new + newoff;
 }
-EXPORT_SYMBOL(__nf_ct_ext_add);
+EXPORT_SYMBOL(__nf_ct_ext_add_length);
 
 static void update_alloc_size(struct nf_ct_ext_type *type)
 {

net/netfilter/nf_conntrack_ftp.c

@@ -358,7 +358,7 @@ static int help(struct sk_buff *skb,
 	u32 seq;
 	int dir = CTINFO2DIR(ctinfo);
 	unsigned int uninitialized_var(matchlen), uninitialized_var(matchoff);
-	struct nf_ct_ftp_master *ct_ftp_info = &nfct_help(ct)->help.ct_ftp_info;
+	struct nf_ct_ftp_master *ct_ftp_info = nfct_help_data(ct);
 	struct nf_conntrack_expect *exp;
 	union nf_inet_addr *daddr;
 	struct nf_conntrack_man cmd = {};
@@ -512,7 +512,6 @@ static int help(struct sk_buff *skb,
 }
 
 static struct nf_conntrack_helper ftp[MAX_PORTS][2] __read_mostly;
-static char ftp_names[MAX_PORTS][2][sizeof("ftp-65535")] __read_mostly;
 
 static const struct nf_conntrack_expect_policy ftp_exp_policy = {
 	.max_expected	= 1,
@@ -541,7 +540,6 @@ static void nf_conntrack_ftp_fini(void)
 static int __init nf_conntrack_ftp_init(void)
 {
 	int i, j = -1, ret = 0;
-	char *tmpname;
 
 	ftp_buffer = kmalloc(65536, GFP_KERNEL);
 	if (!ftp_buffer)
@@ -556,17 +554,16 @@ static int __init nf_conntrack_ftp_init(void)
 		ftp[i][0].tuple.src.l3num = PF_INET;
 		ftp[i][1].tuple.src.l3num = PF_INET6;
 		for (j = 0; j < 2; j++) {
+			ftp[i][j].data_len = sizeof(struct nf_ct_ftp_master);
 			ftp[i][j].tuple.src.u.tcp.port = htons(ports[i]);
 			ftp[i][j].tuple.dst.protonum = IPPROTO_TCP;
 			ftp[i][j].expect_policy = &ftp_exp_policy;
 			ftp[i][j].me = THIS_MODULE;
 			ftp[i][j].help = help;
-			tmpname = &ftp_names[i][j][0];
 			if (ports[i] == FTP_PORT)
-				sprintf(tmpname, "ftp");
+				sprintf(ftp[i][j].name, "ftp");
 			else
-				sprintf(tmpname, "ftp-%d", ports[i]);
-			ftp[i][j].name = tmpname;
+				sprintf(ftp[i][j].name, "ftp-%d", ports[i]);
 
 			pr_debug("nf_ct_ftp: registering helper for pf: %d "
 				 "port: %d\n",

net/netfilter/nf_conntrack_h323_main.c

@@ -114,7 +114,7 @@ static int get_tpkt_data(struct sk_buff *skb, unsigned int protoff,
 			 struct nf_conn *ct, enum ip_conntrack_info ctinfo,
 			 unsigned char **data, int *datalen, int *dataoff)
 {
-	struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
+	struct nf_ct_h323_master *info = nfct_help_data(ct);
 	int dir = CTINFO2DIR(ctinfo);
 	const struct tcphdr *th;
 	struct tcphdr _tcph;
@@ -617,6 +617,7 @@ static const struct nf_conntrack_expect_policy h245_exp_policy = {
 static struct nf_conntrack_helper nf_conntrack_helper_h245 __read_mostly = {
 	.name			= "H.245",
 	.me			= THIS_MODULE,
+	.data_len		= sizeof(struct nf_ct_h323_master),
 	.tuple.src.l3num	= AF_UNSPEC,
 	.tuple.dst.protonum	= IPPROTO_UDP,
 	.help			= h245_help,
@@ -1169,6 +1170,7 @@ static struct nf_conntrack_helper nf_conntrack_helper_q931[] __read_mostly = {
 	{
 		.name			= "Q.931",
 		.me			= THIS_MODULE,
+		.data_len		= sizeof(struct nf_ct_h323_master),
 		.tuple.src.l3num	= AF_INET,
 		.tuple.src.u.tcp.port	= cpu_to_be16(Q931_PORT),
 		.tuple.dst.protonum	= IPPROTO_TCP,
@@ -1244,7 +1246,7 @@ static int expect_q931(struct sk_buff *skb, struct nf_conn *ct,
 		       unsigned char **data,
 		       TransportAddress *taddr, int count)
 {
-	struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
+	struct nf_ct_h323_master *info = nfct_help_data(ct);
 	int dir = CTINFO2DIR(ctinfo);
 	int ret = 0;
 	int i;
@@ -1359,7 +1361,7 @@ static int process_rrq(struct sk_buff *skb, struct nf_conn *ct,
 		       enum ip_conntrack_info ctinfo,
 		       unsigned char **data, RegistrationRequest *rrq)
 {
-	struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
+	struct nf_ct_h323_master *info = nfct_help_data(ct);
 	int ret;
 	typeof(set_ras_addr_hook) set_ras_addr;
 
@@ -1394,7 +1396,7 @@ static int process_rcf(struct sk_buff *skb, struct nf_conn *ct,
 		       enum ip_conntrack_info ctinfo,
 		       unsigned char **data, RegistrationConfirm *rcf)
 {
-	struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
+	struct nf_ct_h323_master *info = nfct_help_data(ct);
 	int dir = CTINFO2DIR(ctinfo);
 	int ret;
 	struct nf_conntrack_expect *exp;
@@ -1443,7 +1445,7 @@ static int process_urq(struct sk_buff *skb, struct nf_conn *ct,
 		       enum ip_conntrack_info ctinfo,
 		       unsigned char **data, UnregistrationRequest *urq)
 {
-	struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
+	struct nf_ct_h323_master *info = nfct_help_data(ct);
 	int dir = CTINFO2DIR(ctinfo);
 	int ret;
 	typeof(set_sig_addr_hook) set_sig_addr;
@@ -1475,7 +1477,7 @@ static int process_arq(struct sk_buff *skb, struct nf_conn *ct,
 		       enum ip_conntrack_info ctinfo,
 		       unsigned char **data, AdmissionRequest *arq)
 {
-	const struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
+	const struct nf_ct_h323_master *info = nfct_help_data(ct);
 	int dir = CTINFO2DIR(ctinfo);
 	__be16 port;
 	union nf_inet_addr addr;
@@ -1742,6 +1744,7 @@ static struct nf_conntrack_helper nf_conntrack_helper_ras[] __read_mostly = {
 	{
 		.name			= "RAS",
 		.me			= THIS_MODULE,
+		.data_len		= sizeof(struct nf_ct_h323_master),
 		.tuple.src.l3num	= AF_INET,
 		.tuple.src.u.udp.port	= cpu_to_be16(RAS_PORT),
 		.tuple.dst.protonum	= IPPROTO_UDP,
@@ -1751,6 +1754,7 @@ static struct nf_conntrack_helper nf_conntrack_helper_ras[] __read_mostly = {
 	{
 		.name			= "RAS",
 		.me			= THIS_MODULE,
+		.data_len		= sizeof(struct nf_ct_h323_master),
 		.tuple.src.l3num	= AF_INET6,
 		.tuple.src.u.udp.port	= cpu_to_be16(RAS_PORT),
 		.tuple.dst.protonum	= IPPROTO_UDP,

net/netfilter/nf_conntrack_helper.c

@@ -30,8 +30,10 @@
 #include <net/netfilter/nf_conntrack_extend.h>
 
 static DEFINE_MUTEX(nf_ct_helper_mutex);
-static struct hlist_head *nf_ct_helper_hash __read_mostly;
-static unsigned int nf_ct_helper_hsize __read_mostly;
+struct hlist_head *nf_ct_helper_hash __read_mostly;
+EXPORT_SYMBOL_GPL(nf_ct_helper_hash);
+unsigned int nf_ct_helper_hsize __read_mostly;
+EXPORT_SYMBOL_GPL(nf_ct_helper_hsize);
 static unsigned int nf_ct_helper_count __read_mostly;
 
 static bool nf_ct_auto_assign_helper __read_mostly = true;
@@ -161,11 +163,14 @@ nf_conntrack_helper_try_module_get(const char *name, u16 l3num, u8 protonum)
 }
 EXPORT_SYMBOL_GPL(nf_conntrack_helper_try_module_get);
 
-struct nf_conn_help *nf_ct_helper_ext_add(struct nf_conn *ct, gfp_t gfp)
+struct nf_conn_help *
+nf_ct_helper_ext_add(struct nf_conn *ct,
+		     struct nf_conntrack_helper *helper, gfp_t gfp)
 {
 	struct nf_conn_help *help;
 
-	help = nf_ct_ext_add(ct, NF_CT_EXT_HELPER, gfp);
+	help = nf_ct_ext_add_length(ct, NF_CT_EXT_HELPER,
+				    helper->data_len, gfp);
 	if (help)
 		INIT_HLIST_HEAD(&help->expectations);
 	else
@@ -218,13 +223,13 @@ int __nf_ct_try_assign_helper(struct nf_conn *ct, struct nf_conn *tmpl,
 	}
 
 	if (help == NULL) {
-		help = nf_ct_helper_ext_add(ct, flags);
+		help = nf_ct_helper_ext_add(ct, helper, flags);
 		if (help == NULL) {
 			ret = -ENOMEM;
 			goto out;
 		}
 	} else {
-		memset(&help->help, 0, sizeof(help->help));
+		memset(help->data, 0, helper->data_len);
 	}
 
 	rcu_assign_pointer(help->helper, helper);
@@ -319,6 +324,9 @@ EXPORT_SYMBOL_GPL(nf_ct_helper_expectfn_find_by_symbol);
 
 int nf_conntrack_helper_register(struct nf_conntrack_helper *me)
 {
+	int ret = 0;
+	struct nf_conntrack_helper *cur;
+	struct hlist_node *n;
 	unsigned int h = helper_hash(&me->tuple);
 
 	BUG_ON(me->expect_policy == NULL);
@@ -326,11 +334,19 @@ int nf_conntrack_helper_register(struct nf_conntrack_helper *me)
 	BUG_ON(strlen(me->name) > NF_CT_HELPER_NAME_LEN - 1);
 
 	mutex_lock(&nf_ct_helper_mutex);
+	hlist_for_each_entry(cur, n, &nf_ct_helper_hash[h], hnode) {
+		if (strncmp(cur->name, me->name, NF_CT_HELPER_NAME_LEN) == 0 &&
+		    cur->tuple.src.l3num == me->tuple.src.l3num &&
+		    cur->tuple.dst.protonum == me->tuple.dst.protonum) {
+			ret = -EEXIST;
+			goto out;
+		}
+	}
 	hlist_add_head_rcu(&me->hnode, &nf_ct_helper_hash[h]);
 	nf_ct_helper_count++;
+out:
 	mutex_unlock(&nf_ct_helper_mutex);
-
-	return 0;
+	return ret;
 }
 EXPORT_SYMBOL_GPL(nf_conntrack_helper_register);
 

net/netfilter/nf_conntrack_irc.c

@@ -221,7 +221,6 @@ static int help(struct sk_buff *skb, unsigned int protoff,
 }
 
 static struct nf_conntrack_helper irc[MAX_PORTS] __read_mostly;
-static char irc_names[MAX_PORTS][sizeof("irc-65535")] __read_mostly;
 static struct nf_conntrack_expect_policy irc_exp_policy;
 
 static void nf_conntrack_irc_fini(void);
@@ -229,7 +228,6 @@ static void nf_conntrack_irc_fini(void);
 static int __init nf_conntrack_irc_init(void)
 {
 	int i, ret;
-	char *tmpname;
 
 	if (max_dcc_channels < 1) {
 		printk(KERN_ERR "nf_ct_irc: max_dcc_channels must not be zero\n");
@@ -255,12 +253,10 @@ static int __init nf_conntrack_irc_init(void)
 		irc[i].me = THIS_MODULE;
 		irc[i].help = help;
 
-		tmpname = &irc_names[i][0];
 		if (ports[i] == IRC_PORT)
-			sprintf(tmpname, "irc");
+			sprintf(irc[i].name, "irc");
 		else
-			sprintf(tmpname, "irc-%u", i);
-		irc[i].name = tmpname;
+			sprintf(irc[i].name, "irc-%u", i);
 
 		ret = nf_conntrack_helper_register(&irc[i]);
 		if (ret) {

net/netfilter/nf_conntrack_netlink.c

@@ -46,6 +46,7 @@
 #ifdef CONFIG_NF_NAT_NEEDED
 #include <net/netfilter/nf_nat_core.h>
 #include <net/netfilter/nf_nat_protocol.h>
+#include <net/netfilter/nf_nat_helper.h>
 #endif
 
 #include <linux/netfilter/nfnetlink.h>
@@ -901,7 +902,8 @@ static const struct nla_policy help_nla_policy[CTA_HELP_MAX+1] = {
 };
 
 static inline int
-ctnetlink_parse_help(const struct nlattr *attr, char **helper_name)
+ctnetlink_parse_help(const struct nlattr *attr, char **helper_name,
+		     struct nlattr **helpinfo)
 {
 	struct nlattr *tb[CTA_HELP_MAX+1];
 
@@ -912,6 +914,9 @@ ctnetlink_parse_help(const struct nlattr *attr, char **helper_name)
 
 	*helper_name = nla_data(tb[CTA_HELP_NAME]);
 
+	if (tb[CTA_HELP_INFO])
+		*helpinfo = tb[CTA_HELP_INFO];
+
 	return 0;
 }
 
@@ -1172,13 +1177,14 @@ ctnetlink_change_helper(struct nf_conn *ct, const struct nlattr * const cda[])
 	struct nf_conntrack_helper *helper;
 	struct nf_conn_help *help = nfct_help(ct);
 	char *helpname = NULL;
+	struct nlattr *helpinfo = NULL;
 	int err;
 
 	/* don't change helper of sibling connections */
 	if (ct->master)
 		return -EBUSY;
 
-	err = ctnetlink_parse_help(cda[CTA_HELP], &helpname);
+	err = ctnetlink_parse_help(cda[CTA_HELP], &helpname, &helpinfo);
 	if (err < 0)
 		return err;
 
@@ -1213,12 +1219,16 @@ ctnetlink_change_helper(struct nf_conn *ct, const struct nlattr * const cda[])
 	}
 
 	if (help) {
-		if (help->helper == helper)
+		if (help->helper == helper) {
+			/* update private helper data if allowed. */
+			if (helper->from_nlattr && helpinfo)
+				helper->from_nlattr(helpinfo, ct);
 			return 0;
+		}
 		if (help->helper)
 			return -EBUSY;
 		/* need to zero data of old helper */
-		memset(&help->help, 0, sizeof(help->help));
+		memset(help->data, 0, help->helper->data_len);
 	} else {
 		/* we cannot set a helper for an existing conntrack */
 		return -EOPNOTSUPP;
@@ -1410,8 +1420,9 @@ ctnetlink_create_conntrack(struct net *net, u16 zone,
 	rcu_read_lock();
  	if (cda[CTA_HELP]) {
 		char *helpname = NULL;
+		struct nlattr *helpinfo = NULL;
 
- 		err = ctnetlink_parse_help(cda[CTA_HELP], &helpname);
+		err = ctnetlink_parse_help(cda[CTA_HELP], &helpname, &helpinfo);
  		if (err < 0)
 			goto err2;
 
@@ -1440,11 +1451,14 @@ ctnetlink_create_conntrack(struct net *net, u16 zone,
 		} else {
 			struct nf_conn_help *help;
 
-			help = nf_ct_helper_ext_add(ct, GFP_ATOMIC);
+			help = nf_ct_helper_ext_add(ct, helper, GFP_ATOMIC);
 			if (help == NULL) {
 				err = -ENOMEM;
 				goto err2;
 			}
+			/* set private helper data if allowed. */
+			if (helper->from_nlattr && helpinfo)
+				helper->from_nlattr(helpinfo, ct);
 
 			/* not in hash table yet so not strictly necessary */
 			RCU_INIT_POINTER(help->helper, helper);
@@ -1620,6 +1634,143 @@ ctnetlink_new_conntrack(struct sock *ctnl, struct sk_buff *skb,
 	return err;
 }
 
+#if defined(CONFIG_NETFILTER_NETLINK_QUEUE) ||	\
+    defined(CONFIG_NETFILTER_NETLINK_QUEUE_MODULE)
+static size_t
+ctnetlink_nfqueue_build_size(const struct nf_conn *ct)
+{
+	return 3 * nla_total_size(0) /* CTA_TUPLE_ORIG|REPL|MASTER */
+	       + 3 * nla_total_size(0) /* CTA_TUPLE_IP */
+	       + 3 * nla_total_size(0) /* CTA_TUPLE_PROTO */
+	       + 3 * nla_total_size(sizeof(u_int8_t)) /* CTA_PROTO_NUM */
+	       + nla_total_size(sizeof(u_int32_t)) /* CTA_ID */
+	       + nla_total_size(sizeof(u_int32_t)) /* CTA_STATUS */
+	       + nla_total_size(sizeof(u_int32_t)) /* CTA_TIMEOUT */
+	       + nla_total_size(0) /* CTA_PROTOINFO */
+	       + nla_total_size(0) /* CTA_HELP */
+	       + nla_total_size(NF_CT_HELPER_NAME_LEN) /* CTA_HELP_NAME */
+	       + ctnetlink_secctx_size(ct)
+#ifdef CONFIG_NF_NAT_NEEDED
+	       + 2 * nla_total_size(0) /* CTA_NAT_SEQ_ADJ_ORIG|REPL */
+	       + 6 * nla_total_size(sizeof(u_int32_t)) /* CTA_NAT_SEQ_OFFSET */
+#endif
+#ifdef CONFIG_NF_CONNTRACK_MARK
+	       + nla_total_size(sizeof(u_int32_t)) /* CTA_MARK */
+#endif
+	       + ctnetlink_proto_size(ct)
+	       ;
+}
+
+static int
+ctnetlink_nfqueue_build(struct sk_buff *skb, struct nf_conn *ct)
+{
+	struct nlattr *nest_parms;
+
+	rcu_read_lock();
+	nest_parms = nla_nest_start(skb, CTA_TUPLE_ORIG | NLA_F_NESTED);
+	if (!nest_parms)
+		goto nla_put_failure;
+	if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
+		goto nla_put_failure;
+	nla_nest_end(skb, nest_parms);
+
+	nest_parms = nla_nest_start(skb, CTA_TUPLE_REPLY | NLA_F_NESTED);
+	if (!nest_parms)
+		goto nla_put_failure;
+	if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_REPLY)) < 0)
+		goto nla_put_failure;
+	nla_nest_end(skb, nest_parms);
+
+	if (nf_ct_zone(ct)) {
+		if (nla_put_be16(skb, CTA_ZONE, htons(nf_ct_zone(ct))))
+			goto nla_put_failure;
+	}
+
+	if (ctnetlink_dump_id(skb, ct) < 0)
+		goto nla_put_failure;
+
+	if (ctnetlink_dump_status(skb, ct) < 0)
+		goto nla_put_failure;
+
+	if (ctnetlink_dump_timeout(skb, ct) < 0)
+		goto nla_put_failure;
+
+	if (ctnetlink_dump_protoinfo(skb, ct) < 0)
+		goto nla_put_failure;
+
+	if (ctnetlink_dump_helpinfo(skb, ct) < 0)
+		goto nla_put_failure;
+
+#ifdef CONFIG_NF_CONNTRACK_SECMARK
+	if (ct->secmark && ctnetlink_dump_secctx(skb, ct) < 0)
+		goto nla_put_failure;
+#endif
+	if (ct->master && ctnetlink_dump_master(skb, ct) < 0)
+		goto nla_put_failure;
+
+	if ((ct->status & IPS_SEQ_ADJUST) &&
+	    ctnetlink_dump_nat_seq_adj(skb, ct) < 0)
+		goto nla_put_failure;
+
+#ifdef CONFIG_NF_CONNTRACK_MARK
+	if (ct->mark && ctnetlink_dump_mark(skb, ct) < 0)
+		goto nla_put_failure;
+#endif
+	rcu_read_unlock();
+	return 0;
+
+nla_put_failure:
+	rcu_read_unlock();
+	return -ENOSPC;
+}
+
+static int
+ctnetlink_nfqueue_parse_ct(const struct nlattr *cda[], struct nf_conn *ct)
+{
+	int err;
+
+	if (cda[CTA_TIMEOUT]) {
+		err = ctnetlink_change_timeout(ct, cda);
+		if (err < 0)
+			return err;
+	}
+	if (cda[CTA_STATUS]) {
+		err = ctnetlink_change_status(ct, cda);
+		if (err < 0)
+			return err;
+	}
+	if (cda[CTA_HELP]) {
+		err = ctnetlink_change_helper(ct, cda);
+		if (err < 0)
+			return err;
+	}
+#if defined(CONFIG_NF_CONNTRACK_MARK)
+	if (cda[CTA_MARK])
+		ct->mark = ntohl(nla_get_be32(cda[CTA_MARK]));
+#endif
+	return 0;
+}
+
+static int
+ctnetlink_nfqueue_parse(const struct nlattr *attr, struct nf_conn *ct)
+{
+	struct nlattr *cda[CTA_MAX+1];
+
+	nla_parse_nested(cda, CTA_MAX, attr, ct_nla_policy);
+
+	return ctnetlink_nfqueue_parse_ct((const struct nlattr **)cda, ct);
+}
+
+static struct nfq_ct_hook ctnetlink_nfqueue_hook = {
+	.build_size	= ctnetlink_nfqueue_build_size,
+	.build		= ctnetlink_nfqueue_build,
+	.parse		= ctnetlink_nfqueue_parse,
+#ifdef CONFIG_NF_NAT_NEEDED
+	.seq_adjust	= nf_nat_tcp_seq_adjust,
+#endif
+};
+#endif /* CONFIG_NETFILTER_NETLINK_QUEUE */
+
 /***********************************************************************
  * EXPECT
  ***********************************************************************/
@@ -2424,7 +2575,11 @@ static int __init ctnetlink_init(void)
 		pr_err("ctnetlink_init: cannot register pernet operations\n");
 		goto err_unreg_exp_subsys;
 	}
-
+#if defined(CONFIG_NETFILTER_NETLINK_QUEUE) ||	\
+    defined(CONFIG_NETFILTER_NETLINK_QUEUE_MODULE)
+	/* setup interaction between nf_queue and nf_conntrack_netlink. */
+	RCU_INIT_POINTER(nfq_ct_hook, &ctnetlink_nfqueue_hook);
+#endif
 	return 0;
 
 err_unreg_exp_subsys:
@@ -2442,6 +2597,10 @@ static void __exit ctnetlink_exit(void)
 	unregister_pernet_subsys(&ctnetlink_net_ops);
 	nfnetlink_subsys_unregister(&ctnl_exp_subsys);
 	nfnetlink_subsys_unregister(&ctnl_subsys);
+#if defined(CONFIG_NETFILTER_NETLINK_QUEUE) ||	\
+    defined(CONFIG_NETFILTER_NETLINK_QUEUE_MODULE)
+	RCU_INIT_POINTER(nfq_ct_hook, NULL);
+#endif
 }
 
 module_init(ctnetlink_init);

net/netfilter/nf_conntrack_pptp.c

@@ -174,7 +174,7 @@ static int destroy_sibling_or_exp(struct net *net, struct nf_conn *ct,
 static void pptp_destroy_siblings(struct nf_conn *ct)
 {
 	struct net *net = nf_ct_net(ct);
-	const struct nf_conn_help *help = nfct_help(ct);
+	const struct nf_ct_pptp_master *ct_pptp_info = nfct_help_data(ct);
 	struct nf_conntrack_tuple t;
 
 	nf_ct_gre_keymap_destroy(ct);
@@ -182,16 +182,16 @@ static void pptp_destroy_siblings(struct nf_conn *ct)
 	/* try original (pns->pac) tuple */
 	memcpy(&t, &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple, sizeof(t));
 	t.dst.protonum = IPPROTO_GRE;
-	t.src.u.gre.key = help->help.ct_pptp_info.pns_call_id;
-	t.dst.u.gre.key = help->help.ct_pptp_info.pac_call_id;
+	t.src.u.gre.key = ct_pptp_info->pns_call_id;
+	t.dst.u.gre.key = ct_pptp_info->pac_call_id;
 	if (!destroy_sibling_or_exp(net, ct, &t))
 		pr_debug("failed to timeout original pns->pac ct/exp\n");
 
 	/* try reply (pac->pns) tuple */
 	memcpy(&t, &ct->tuplehash[IP_CT_DIR_REPLY].tuple, sizeof(t));
 	t.dst.protonum = IPPROTO_GRE;
-	t.src.u.gre.key = help->help.ct_pptp_info.pac_call_id;
-	t.dst.u.gre.key = help->help.ct_pptp_info.pns_call_id;
+	t.src.u.gre.key = ct_pptp_info->pac_call_id;
+	t.dst.u.gre.key = ct_pptp_info->pns_call_id;
 	if (!destroy_sibling_or_exp(net, ct, &t))
 		pr_debug("failed to timeout reply pac->pns ct/exp\n");
 }
@@ -269,7 +269,7 @@ pptp_inbound_pkt(struct sk_buff *skb,
 		 struct nf_conn *ct,
 		 enum ip_conntrack_info ctinfo)
 {
-	struct nf_ct_pptp_master *info = &nfct_help(ct)->help.ct_pptp_info;
+	struct nf_ct_pptp_master *info = nfct_help_data(ct);
 	u_int16_t msg;
 	__be16 cid = 0, pcid = 0;
 	typeof(nf_nat_pptp_hook_inbound) nf_nat_pptp_inbound;
@@ -396,7 +396,7 @@ pptp_outbound_pkt(struct sk_buff *skb,
 		  struct nf_conn *ct,
 		  enum ip_conntrack_info ctinfo)
 {
-	struct nf_ct_pptp_master *info = &nfct_help(ct)->help.ct_pptp_info;
+	struct nf_ct_pptp_master *info = nfct_help_data(ct);
 	u_int16_t msg;
 	__be16 cid = 0, pcid = 0;
 	typeof(nf_nat_pptp_hook_outbound) nf_nat_pptp_outbound;
@@ -506,7 +506,7 @@ conntrack_pptp_help(struct sk_buff *skb, unsigned int protoff,
 
 {
 	int dir = CTINFO2DIR(ctinfo);
-	const struct nf_ct_pptp_master *info = &nfct_help(ct)->help.ct_pptp_info;
+	const struct nf_ct_pptp_master *info = nfct_help_data(ct);
 	const struct tcphdr *tcph;
 	struct tcphdr _tcph;
 	const struct pptp_pkt_hdr *pptph;
@@ -592,6 +592,7 @@ static const struct nf_conntrack_expect_policy pptp_exp_policy = {
 static struct nf_conntrack_helper pptp __read_mostly = {
 	.name			= "pptp",
 	.me			= THIS_MODULE,
+	.data_len		= sizeof(struct nf_ct_pptp_master),
 	.tuple.src.l3num	= AF_INET,
 	.tuple.src.u.tcp.port	= cpu_to_be16(PPTP_CONTROL_PORT),
 	.tuple.dst.protonum	= IPPROTO_TCP,

net/netfilter/nf_conntrack_proto_gre.c

@@ -117,10 +117,10 @@ int nf_ct_gre_keymap_add(struct nf_conn *ct, enum ip_conntrack_dir dir,
 {
 	struct net *net = nf_ct_net(ct);
 	struct netns_proto_gre *net_gre = gre_pernet(net);
-	struct nf_conn_help *help = nfct_help(ct);
+	struct nf_ct_pptp_master *ct_pptp_info = nfct_help_data(ct);
 	struct nf_ct_gre_keymap **kmp, *km;
 
-	kmp = &help->help.ct_pptp_info.keymap[dir];
+	kmp = &ct_pptp_info->keymap[dir];
 	if (*kmp) {
 		/* check whether it's a retransmission */
 		read_lock_bh(&net_gre->keymap_lock);
@@ -158,19 +158,19 @@ void nf_ct_gre_keymap_destroy(struct nf_conn *ct)
 {
 	struct net *net = nf_ct_net(ct);
 	struct netns_proto_gre *net_gre = gre_pernet(net);
-	struct nf_conn_help *help = nfct_help(ct);
+	struct nf_ct_pptp_master *ct_pptp_info = nfct_help_data(ct);
 	enum ip_conntrack_dir dir;
 
 	pr_debug("entering for ct %p\n", ct);
 
 	write_lock_bh(&net_gre->keymap_lock);
 	for (dir = IP_CT_DIR_ORIGINAL; dir < IP_CT_DIR_MAX; dir++) {
-		if (help->help.ct_pptp_info.keymap[dir]) {
+		if (ct_pptp_info->keymap[dir]) {
 			pr_debug("removing %p from list\n",
-				 help->help.ct_pptp_info.keymap[dir]);
-			list_del(&help->help.ct_pptp_info.keymap[dir]->list);
-			kfree(help->help.ct_pptp_info.keymap[dir]);
-			help->help.ct_pptp_info.keymap[dir] = NULL;
+				 ct_pptp_info->keymap[dir]);
+			list_del(&ct_pptp_info->keymap[dir]->list);
+			kfree(ct_pptp_info->keymap[dir]);
+			ct_pptp_info->keymap[dir] = NULL;
 		}
 	}
 	write_unlock_bh(&net_gre->keymap_lock);

net/netfilter/nf_conntrack_sane.c

@@ -69,13 +69,12 @@ static int help(struct sk_buff *skb,
 	void *sb_ptr;
 	int ret = NF_ACCEPT;
 	int dir = CTINFO2DIR(ctinfo);
-	struct nf_ct_sane_master *ct_sane_info;
+	struct nf_ct_sane_master *ct_sane_info = nfct_help_data(ct);
 	struct nf_conntrack_expect *exp;
 	struct nf_conntrack_tuple *tuple;
 	struct sane_request *req;
 	struct sane_reply_net_start *reply;
 
-	ct_sane_info = &nfct_help(ct)->help.ct_sane_info;
 	/* Until there's been traffic both ways, don't look in packets. */
 	if (ctinfo != IP_CT_ESTABLISHED &&
 	    ctinfo != IP_CT_ESTABLISHED_REPLY)
@@ -163,7 +162,6 @@ static int help(struct sk_buff *skb,
 }
 
 static struct nf_conntrack_helper sane[MAX_PORTS][2] __read_mostly;
-static char sane_names[MAX_PORTS][2][sizeof("sane-65535")] __read_mostly;
 
 static const struct nf_conntrack_expect_policy sane_exp_policy = {
 	.max_expected	= 1,
@@ -190,7 +188,6 @@ static void nf_conntrack_sane_fini(void)
 static int __init nf_conntrack_sane_init(void)
 {
 	int i, j = -1, ret = 0;
-	char *tmpname;
 
 	sane_buffer = kmalloc(65536, GFP_KERNEL);
 	if (!sane_buffer)
@@ -205,17 +202,16 @@ static int __init nf_conntrack_sane_init(void)
 		sane[i][0].tuple.src.l3num = PF_INET;
 		sane[i][1].tuple.src.l3num = PF_INET6;
 		for (j = 0; j < 2; j++) {
+			sane[i][j].data_len = sizeof(struct nf_ct_sane_master);
 			sane[i][j].tuple.src.u.tcp.port = htons(ports[i]);
 			sane[i][j].tuple.dst.protonum = IPPROTO_TCP;
 			sane[i][j].expect_policy = &sane_exp_policy;
 			sane[i][j].me = THIS_MODULE;
 			sane[i][j].help = help;
-			tmpname = &sane_names[i][j][0];
 			if (ports[i] == SANE_PORT)
-				sprintf(tmpname, "sane");
+				sprintf(sane[i][j].name, "sane");
 			else
-				sprintf(tmpname, "sane-%d", ports[i]);
-			sane[i][j].name = tmpname;
+				sprintf(sane[i][j].name, "sane-%d", ports[i]);
 
 			pr_debug("nf_ct_sane: registering helper for pf: %d "
 				 "port: %d\n",

net/netfilter/nf_conntrack_sip.c

@@ -1075,12 +1075,12 @@ static int process_invite_response(struct sk_buff *skb, unsigned int dataoff,
 {
 	enum ip_conntrack_info ctinfo;
 	struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
-	struct nf_conn_help *help = nfct_help(ct);
+	struct nf_ct_sip_master *ct_sip_info = nfct_help_data(ct);
 
 	if ((code >= 100 && code <= 199) ||
 	    (code >= 200 && code <= 299))
 		return process_sdp(skb, dataoff, dptr, datalen, cseq);
-	else if (help->help.ct_sip_info.invite_cseq == cseq)
+	else if (ct_sip_info->invite_cseq == cseq)
 		flush_expectations(ct, true);
 	return NF_ACCEPT;
 }
@@ -1091,12 +1091,12 @@ static int process_update_response(struct sk_buff *skb, unsigned int dataoff,
 {
 	enum ip_conntrack_info ctinfo;
 	struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
-	struct nf_conn_help *help = nfct_help(ct);
+	struct nf_ct_sip_master *ct_sip_info = nfct_help_data(ct);
 
 	if ((code >= 100 && code <= 199) ||
 	    (code >= 200 && code <= 299))
 		return process_sdp(skb, dataoff, dptr, datalen, cseq);
-	else if (help->help.ct_sip_info.invite_cseq == cseq)
+	else if (ct_sip_info->invite_cseq == cseq)
 		flush_expectations(ct, true);
 	return NF_ACCEPT;
 }
@@ -1107,12 +1107,12 @@ static int process_prack_response(struct sk_buff *skb, unsigned int dataoff,
 {
 	enum ip_conntrack_info ctinfo;
 	struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
-	struct nf_conn_help *help = nfct_help(ct);
+	struct nf_ct_sip_master *ct_sip_info = nfct_help_data(ct);
 
 	if ((code >= 100 && code <= 199) ||
 	    (code >= 200 && code <= 299))
 		return process_sdp(skb, dataoff, dptr, datalen, cseq);
-	else if (help->help.ct_sip_info.invite_cseq == cseq)
+	else if (ct_sip_info->invite_cseq == cseq)
 		flush_expectations(ct, true);
 	return NF_ACCEPT;
 }
@@ -1123,13 +1123,13 @@ static int process_invite_request(struct sk_buff *skb, unsigned int dataoff,
 {
 	enum ip_conntrack_info ctinfo;
 	struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
-	struct nf_conn_help *help = nfct_help(ct);
+	struct nf_ct_sip_master *ct_sip_info = nfct_help_data(ct);
 	unsigned int ret;
 
 	flush_expectations(ct, true);
 	ret = process_sdp(skb, dataoff, dptr, datalen, cseq);
 	if (ret == NF_ACCEPT)
-		help->help.ct_sip_info.invite_cseq = cseq;
+		ct_sip_info->invite_cseq = cseq;
 	return ret;
 }
 
@@ -1154,7 +1154,7 @@ static int process_register_request(struct sk_buff *skb, unsigned int dataoff,
 {
 	enum ip_conntrack_info ctinfo;
 	struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
-	struct nf_conn_help *help = nfct_help(ct);
+	struct nf_ct_sip_master *ct_sip_info = nfct_help_data(ct);
 	enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
 	unsigned int matchoff, matchlen;
 	struct nf_conntrack_expect *exp;
@@ -1235,7 +1235,7 @@ static int process_register_request(struct sk_buff *skb, unsigned int dataoff,
 
 store_cseq:
 	if (ret == NF_ACCEPT)
-		help->help.ct_sip_info.register_cseq = cseq;
+		ct_sip_info->register_cseq = cseq;
 	return ret;
 }
 
@@ -1245,7 +1245,7 @@ static int process_register_response(struct sk_buff *skb, unsigned int dataoff,
 {
 	enum ip_conntrack_info ctinfo;
 	struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
-	struct nf_conn_help *help = nfct_help(ct);
+	struct nf_ct_sip_master *ct_sip_info = nfct_help_data(ct);
 	enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
 	union nf_inet_addr addr;
 	__be16 port;
@@ -1262,7 +1262,7 @@ static int process_register_response(struct sk_buff *skb, unsigned int dataoff,
 	 * responses, so we store the sequence number of the last valid
 	 * request and compare it here.
 	 */
-	if (help->help.ct_sip_info.register_cseq != cseq)
+	if (ct_sip_info->register_cseq != cseq)
 		return NF_ACCEPT;
 
 	if (code >= 100 && code <= 199)
@@ -1556,7 +1556,6 @@ static void nf_conntrack_sip_fini(void)
 static int __init nf_conntrack_sip_init(void)
 {
 	int i, j, ret;
-	char *tmpname;
 
 	if (ports_c == 0)
 		ports[ports_c++] = SIP_PORT;
@@ -1579,17 +1578,16 @@ static int __init nf_conntrack_sip_init(void)
 		sip[i][3].help = sip_help_tcp;
 
 		for (j = 0; j < ARRAY_SIZE(sip[i]); j++) {
+			sip[i][j].data_len = sizeof(struct nf_ct_sip_master);
 			sip[i][j].tuple.src.u.udp.port = htons(ports[i]);
 			sip[i][j].expect_policy = sip_exp_policy;
 			sip[i][j].expect_class_max = SIP_EXPECT_MAX;
 			sip[i][j].me = THIS_MODULE;
 
-			tmpname = &sip_names[i][j][0];
 			if (ports[i] == SIP_PORT)
-				sprintf(tmpname, "sip");
+				sprintf(sip_names[i][j], "sip");
 			else
-				sprintf(tmpname, "sip-%u", i);
-			sip[i][j].name = tmpname;
+				sprintf(sip_names[i][j], "sip-%u", i);
 
 			pr_debug("port #%u: %u\n", i, ports[i]);
 

net/netfilter/nf_conntrack_tftp.c

@@ -92,7 +92,6 @@ static int tftp_help(struct sk_buff *skb,
 }
 
 static struct nf_conntrack_helper tftp[MAX_PORTS][2] __read_mostly;
-static char tftp_names[MAX_PORTS][2][sizeof("tftp-65535")] __read_mostly;
 
 static const struct nf_conntrack_expect_policy tftp_exp_policy = {
 	.max_expected	= 1,
@@ -112,7 +111,6 @@ static void nf_conntrack_tftp_fini(void)
 static int __init nf_conntrack_tftp_init(void)
 {
 	int i, j, ret;
-	char *tmpname;
 
 	if (ports_c == 0)
 		ports[ports_c++] = TFTP_PORT;
@@ -129,12 +127,10 @@ static int __init nf_conntrack_tftp_init(void)
 			tftp[i][j].me = THIS_MODULE;
 			tftp[i][j].help = tftp_help;
 
-			tmpname = &tftp_names[i][j][0];
 			if (ports[i] == TFTP_PORT)
-				sprintf(tmpname, "tftp");
+				sprintf(tftp[i][j].name, "tftp");
 			else
-				sprintf(tmpname, "tftp-%u", i);
-			tftp[i][j].name = tmpname;
+				sprintf(tftp[i][j].name, "tftp-%u", i);
 
 			ret = nf_conntrack_helper_register(&tftp[i][j]);
 			if (ret) {

net/netfilter/nfnetlink_cthelper.c

+/*
+ * (C) 2012 Pablo Neira Ayuso <pablo@netfilter.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation (or any later at your option).
+ *
+ * This software has been sponsored by Vyatta Inc. <http://www.vyatta.com>
+ */
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/skbuff.h>
+#include <linux/netlink.h>
+#include <linux/rculist.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/list.h>
+#include <linux/errno.h>
+#include <net/netlink.h>
+#include <net/sock.h>
+
+#include <net/netfilter/nf_conntrack_helper.h>
+#include <net/netfilter/nf_conntrack_expect.h>
+#include <net/netfilter/nf_conntrack_ecache.h>
+
+#include <linux/netfilter/nfnetlink.h>
+#include <linux/netfilter/nfnetlink_conntrack.h>
+#include <linux/netfilter/nfnetlink_cthelper.h>
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
+MODULE_DESCRIPTION("nfnl_cthelper: User-space connection tracking helpers");
+
+static int
+nfnl_userspace_cthelper(struct sk_buff *skb, unsigned int protoff,
+			struct nf_conn *ct, enum ip_conntrack_info ctinfo)
+{
+	const struct nf_conn_help *help;
+	struct nf_conntrack_helper *helper;
+
+	help = nfct_help(ct);
+	if (help == NULL)
+		return NF_DROP;
+
+	/* rcu_read_lock()ed by nf_hook_slow */
+	helper = rcu_dereference(help->helper);
+	if (helper == NULL)
+		return NF_DROP;
+
+	/* This is an user-space helper not yet configured, skip. */
+	if ((helper->flags &
+	    (NF_CT_HELPER_F_USERSPACE | NF_CT_HELPER_F_CONFIGURED)) ==
+	     NF_CT_HELPER_F_USERSPACE)
+		return NF_ACCEPT;
+
+	/* If the user-space helper is not available, don't block traffic. */
+	return NF_QUEUE_NR(helper->queue_num) | NF_VERDICT_FLAG_QUEUE_BYPASS;
+}
+
+static const struct nla_policy nfnl_cthelper_tuple_pol[NFCTH_TUPLE_MAX+1] = {
+	[NFCTH_TUPLE_L3PROTONUM] = { .type = NLA_U16, },
+	[NFCTH_TUPLE_L4PROTONUM] = { .type = NLA_U8, },
+};
+
+static int
+nfnl_cthelper_parse_tuple(struct nf_conntrack_tuple *tuple,
+			  const struct nlattr *attr)
+{
+	struct nlattr *tb[NFCTH_TUPLE_MAX+1];
+
+	nla_parse_nested(tb, NFCTH_TUPLE_MAX, attr, nfnl_cthelper_tuple_pol);
+
+	if (!tb[NFCTH_TUPLE_L3PROTONUM] || !tb[NFCTH_TUPLE_L4PROTONUM])
+		return -EINVAL;
+
+	tuple->src.l3num = ntohs(nla_get_u16(tb[NFCTH_TUPLE_L3PROTONUM]));
+	tuple->dst.protonum = nla_get_u8(tb[NFCTH_TUPLE_L4PROTONUM]);
+
+	return 0;
+}
+
+static int
+nfnl_cthelper_from_nlattr(struct nlattr *attr, struct nf_conn *ct)
+{
+	const struct nf_conn_help *help = nfct_help(ct);
+
+	if (help->helper->data_len == 0)
+		return -EINVAL;
+
+	memcpy(&help->data, nla_data(attr), help->helper->data_len);
+	return 0;
+}
+
+static int
+nfnl_cthelper_to_nlattr(struct sk_buff *skb, const struct nf_conn *ct)
+{
+	const struct nf_conn_help *help = nfct_help(ct);
+
+	if (help->helper->data_len &&
+	    nla_put(skb, CTA_HELP_INFO, help->helper->data_len, &help->data))
+		goto nla_put_failure;
+
+	return 0;
+
+nla_put_failure:
+	return -ENOSPC;
+}
+
+static const struct nla_policy nfnl_cthelper_expect_pol[NFCTH_POLICY_MAX+1] = {
+	[NFCTH_POLICY_NAME] = { .type = NLA_NUL_STRING,
+				.len = NF_CT_HELPER_NAME_LEN-1 },
+	[NFCTH_POLICY_EXPECT_MAX] = { .type = NLA_U32, },
+	[NFCTH_POLICY_EXPECT_TIMEOUT] = { .type = NLA_U32, },
+};
+
+static int
+nfnl_cthelper_expect_policy(struct nf_conntrack_expect_policy *expect_policy,
+			    const struct nlattr *attr)
+{
+	struct nlattr *tb[NFCTH_POLICY_MAX+1];
+
+	nla_parse_nested(tb, NFCTH_POLICY_MAX, attr, nfnl_cthelper_expect_pol);
+
+	if (!tb[NFCTH_POLICY_NAME] ||
+	    !tb[NFCTH_POLICY_EXPECT_MAX] ||
+	    !tb[NFCTH_POLICY_EXPECT_TIMEOUT])
+		return -EINVAL;
+
+	strncpy(expect_policy->name,
+		nla_data(tb[NFCTH_POLICY_NAME]), NF_CT_HELPER_NAME_LEN);
+	expect_policy->max_expected =
+		ntohl(nla_get_be32(tb[NFCTH_POLICY_EXPECT_MAX]));
+	expect_policy->timeout =
+		ntohl(nla_get_be32(tb[NFCTH_POLICY_EXPECT_TIMEOUT]));
+
+	return 0;
+}
+
+static const struct nla_policy
+nfnl_cthelper_expect_policy_set[NFCTH_POLICY_SET_MAX+1] = {
+	[NFCTH_POLICY_SET_NUM] = { .type = NLA_U32, },
+};
+
+static int
+nfnl_cthelper_parse_expect_policy(struct nf_conntrack_helper *helper,
+				  const struct nlattr *attr)
+{
+	int i, ret;
+	struct nf_conntrack_expect_policy *expect_policy;
+	struct nlattr *tb[NFCTH_POLICY_SET_MAX+1];
+
+	nla_parse_nested(tb, NFCTH_POLICY_SET_MAX, attr,
+					nfnl_cthelper_expect_policy_set);
+
+	if (!tb[NFCTH_POLICY_SET_NUM])
+		return -EINVAL;
+
+	helper->expect_class_max =
+		ntohl(nla_get_be32(tb[NFCTH_POLICY_SET_NUM]));
+
+	if (helper->expect_class_max != 0 &&
+	    helper->expect_class_max > NF_CT_MAX_EXPECT_CLASSES)
+		return -EOVERFLOW;
+
+	expect_policy = kzalloc(sizeof(struct nf_conntrack_expect_policy) *
+				helper->expect_class_max, GFP_KERNEL);
+	if (expect_policy == NULL)
+		return -ENOMEM;
+
+	for (i=0; i<helper->expect_class_max; i++) {
+		if (!tb[NFCTH_POLICY_SET+i])
+			goto err;
+
+		ret = nfnl_cthelper_expect_policy(&expect_policy[i],
+						  tb[NFCTH_POLICY_SET+i]);
+		if (ret < 0)
+			goto err;
+	}
+	helper->expect_policy = expect_policy;
+	return 0;
+err:
+	kfree(expect_policy);
+	return -EINVAL;
+}
+
+static int
+nfnl_cthelper_create(const struct nlattr * const tb[],
+		     struct nf_conntrack_tuple *tuple)
+{
+	struct nf_conntrack_helper *helper;
+	int ret;
+
+	if (!tb[NFCTH_TUPLE] || !tb[NFCTH_POLICY] || !tb[NFCTH_PRIV_DATA_LEN])
+		return -EINVAL;
+
+	helper = kzalloc(sizeof(struct nf_conntrack_helper), GFP_KERNEL);
+	if (helper == NULL)
+		return -ENOMEM;
+
+	ret = nfnl_cthelper_parse_expect_policy(helper, tb[NFCTH_POLICY]);
+	if (ret < 0)
+		goto err;
+
+	strncpy(helper->name, nla_data(tb[NFCTH_NAME]), NF_CT_HELPER_NAME_LEN);
+	helper->data_len = ntohl(nla_get_be32(tb[NFCTH_PRIV_DATA_LEN]));
+	helper->flags |= NF_CT_HELPER_F_USERSPACE;
+	memcpy(&helper->tuple, tuple, sizeof(struct nf_conntrack_tuple));
+
+	helper->me = THIS_MODULE;
+	helper->help = nfnl_userspace_cthelper;
+	helper->from_nlattr = nfnl_cthelper_from_nlattr;
+	helper->to_nlattr = nfnl_cthelper_to_nlattr;
+
+	/* Default to queue number zero, this can be updated at any time. */
+	if (tb[NFCTH_QUEUE_NUM])
+		helper->queue_num = ntohl(nla_get_be32(tb[NFCTH_QUEUE_NUM]));
+
+	if (tb[NFCTH_STATUS]) {
+		int status = ntohl(nla_get_be32(tb[NFCTH_STATUS]));
+
+		switch(status) {
+		case NFCT_HELPER_STATUS_ENABLED:
+			helper->flags |= NF_CT_HELPER_F_CONFIGURED;
+			break;
+		case NFCT_HELPER_STATUS_DISABLED:
+			helper->flags &= ~NF_CT_HELPER_F_CONFIGURED;
+			break;
+		}
+	}
+
+	ret = nf_conntrack_helper_register(helper);
+	if (ret < 0)
+		goto err;
+
+	return 0;
+err:
+	kfree(helper);
+	return ret;
+}
+
+static int
+nfnl_cthelper_update(const struct nlattr * const tb[],
+		     struct nf_conntrack_helper *helper)
+{
+	int ret;
+
+	if (tb[NFCTH_PRIV_DATA_LEN])
+		return -EBUSY;
+
+	if (tb[NFCTH_POLICY]) {
+		ret = nfnl_cthelper_parse_expect_policy(helper,
+							tb[NFCTH_POLICY]);
+		if (ret < 0)
+			return ret;
+	}
+	if (tb[NFCTH_QUEUE_NUM])
+		helper->queue_num = ntohl(nla_get_be32(tb[NFCTH_QUEUE_NUM]));
+
+	if (tb[NFCTH_STATUS]) {
+		int status = ntohl(nla_get_be32(tb[NFCTH_STATUS]));
+
+		switch(status) {
+		case NFCT_HELPER_STATUS_ENABLED:
+			helper->flags |= NF_CT_HELPER_F_CONFIGURED;
+			break;
+		case NFCT_HELPER_STATUS_DISABLED:
+			helper->flags &= ~NF_CT_HELPER_F_CONFIGURED;
+			break;
+		}
+	}
+	return 0;
+}
+
+static int
+nfnl_cthelper_new(struct sock *nfnl, struct sk_buff *skb,
+		  const struct nlmsghdr *nlh, const struct nlattr * const tb[])
+{
+	const char *helper_name;
+	struct nf_conntrack_helper *cur, *helper = NULL;
+	struct nf_conntrack_tuple tuple;
+	struct hlist_node *n;
+	int ret = 0, i;
+
+	if (!tb[NFCTH_NAME] || !tb[NFCTH_TUPLE])
+		return -EINVAL;
+
+	helper_name = nla_data(tb[NFCTH_NAME]);
+
+	ret = nfnl_cthelper_parse_tuple(&tuple, tb[NFCTH_TUPLE]);
+	if (ret < 0)
+		return ret;
+
+	rcu_read_lock();
+	for (i = 0; i < nf_ct_helper_hsize && !helper; i++) {
+		hlist_for_each_entry_rcu(cur, n, &nf_ct_helper_hash[i], hnode) {
+
+			/* skip non-userspace conntrack helpers. */
+			if (!(cur->flags & NF_CT_HELPER_F_USERSPACE))
+				continue;
+
+			if (strncmp(cur->name, helper_name,
+					NF_CT_HELPER_NAME_LEN) != 0)
+				continue;
+
+			if ((tuple.src.l3num != cur->tuple.src.l3num ||
+			     tuple.dst.protonum != cur->tuple.dst.protonum))
+				continue;
+
+			if (nlh->nlmsg_flags & NLM_F_EXCL) {
+				ret = -EEXIST;
+				goto err;
+			}
+			helper = cur;
+			break;
+		}
+	}
+	rcu_read_unlock();
+
+	if (helper == NULL)
+		ret = nfnl_cthelper_create(tb, &tuple);
+	else
+		ret = nfnl_cthelper_update(tb, helper);
+
+	return ret;
+err:
+	rcu_read_unlock();
+	return ret;
+}
+
+static int
+nfnl_cthelper_dump_tuple(struct sk_buff *skb,
+			 struct nf_conntrack_helper *helper)
+{
+	struct nlattr *nest_parms;
+
+	nest_parms = nla_nest_start(skb, NFCTH_TUPLE | NLA_F_NESTED);
+	if (nest_parms == NULL)
+		goto nla_put_failure;
+
+	if (nla_put_be16(skb, NFCTH_TUPLE_L3PROTONUM,
+			 htons(helper->tuple.src.l3num)))
+		goto nla_put_failure;
+
+	if (nla_put_u8(skb, NFCTH_TUPLE_L4PROTONUM, helper->tuple.dst.protonum))
+		goto nla_put_failure;
+
+	nla_nest_end(skb, nest_parms);
+	return 0;
+
+nla_put_failure:
+	return -1;
+}
+
+static int
+nfnl_cthelper_dump_policy(struct sk_buff *skb,
+			struct nf_conntrack_helper *helper)
+{
+	int i;
+	struct nlattr *nest_parms1, *nest_parms2;
+
+	nest_parms1 = nla_nest_start(skb, NFCTH_POLICY | NLA_F_NESTED);
+	if (nest_parms1 == NULL)
+		goto nla_put_failure;
+
+	if (nla_put_be32(skb, NFCTH_POLICY_SET_NUM,
+			 htonl(helper->expect_class_max)))
+		goto nla_put_failure;
+
+	for (i=0; i<helper->expect_class_max; i++) {
+		nest_parms2 = nla_nest_start(skb,
+				(NFCTH_POLICY_SET+i) | NLA_F_NESTED);
+		if (nest_parms2 == NULL)
+			goto nla_put_failure;
+
+		if (nla_put_string(skb, NFCTH_POLICY_NAME,
+				   helper->expect_policy[i].name))
+			goto nla_put_failure;
+
+		if (nla_put_be32(skb, NFCTH_POLICY_EXPECT_MAX,
+				 htonl(helper->expect_policy[i].max_expected)))
+			goto nla_put_failure;
+
+		if (nla_put_be32(skb, NFCTH_POLICY_EXPECT_TIMEOUT,
+				 htonl(helper->expect_policy[i].timeout)))
+			goto nla_put_failure;
+
+		nla_nest_end(skb, nest_parms2);
+	}
+	nla_nest_end(skb, nest_parms1);
+	return 0;
+
+nla_put_failure:
+	return -1;
+}
+
+static int
+nfnl_cthelper_fill_info(struct sk_buff *skb, u32 pid, u32 seq, u32 type,
+			int event, struct nf_conntrack_helper *helper)
+{
+	struct nlmsghdr *nlh;
+	struct nfgenmsg *nfmsg;
+	unsigned int flags = pid ? NLM_F_MULTI : 0;
+	int status;
+
+	event |= NFNL_SUBSYS_CTHELPER << 8;
+	nlh = nlmsg_put(skb, pid, seq, event, sizeof(*nfmsg), flags);
+	if (nlh == NULL)
+		goto nlmsg_failure;
+
+	nfmsg = nlmsg_data(nlh);
+	nfmsg->nfgen_family = AF_UNSPEC;
+	nfmsg->version = NFNETLINK_V0;
+	nfmsg->res_id = 0;
+
+	if (nla_put_string(skb, NFCTH_NAME, helper->name))
+		goto nla_put_failure;
+
+	if (nla_put_be32(skb, NFCTH_QUEUE_NUM, htonl(helper->queue_num)))
+		goto nla_put_failure;
+
+	if (nfnl_cthelper_dump_tuple(skb, helper) < 0)
+		goto nla_put_failure;
+
+	if (nfnl_cthelper_dump_policy(skb, helper) < 0)
+		goto nla_put_failure;
+
+	if (nla_put_be32(skb, NFCTH_PRIV_DATA_LEN, htonl(helper->data_len)))
+		goto nla_put_failure;
+
+	if (helper->flags & NF_CT_HELPER_F_CONFIGURED)
+		status = NFCT_HELPER_STATUS_ENABLED;
+	else
+		status = NFCT_HELPER_STATUS_DISABLED;
+
+	if (nla_put_be32(skb, NFCTH_STATUS, htonl(status)))
+		goto nla_put_failure;
+
+	nlmsg_end(skb, nlh);
+	return skb->len;
+
+nlmsg_failure:
+nla_put_failure:
+	nlmsg_cancel(skb, nlh);
+	return -1;
+}
+
+static int
+nfnl_cthelper_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
+{
+	struct nf_conntrack_helper *cur, *last;
+	struct hlist_node *n;
+
+	rcu_read_lock();
+	last = (struct nf_conntrack_helper *)cb->args[1];
+	for (; cb->args[0] < nf_ct_helper_hsize; cb->args[0]++) {
+restart:
+		hlist_for_each_entry_rcu(cur, n,
+				&nf_ct_helper_hash[cb->args[0]], hnode) {
+
+			/* skip non-userspace conntrack helpers. */
+			if (!(cur->flags & NF_CT_HELPER_F_USERSPACE))
+				continue;
+
+			if (cb->args[1]) {
+				if (cur != last)
+					continue;
+				cb->args[1] = 0;
+			}
+			if (nfnl_cthelper_fill_info(skb,
+					    NETLINK_CB(cb->skb).pid,
+					    cb->nlh->nlmsg_seq,
+					    NFNL_MSG_TYPE(cb->nlh->nlmsg_type),
+					    NFNL_MSG_CTHELPER_NEW, cur) < 0) {
+				cb->args[1] = (unsigned long)cur;
+				goto out;
+			}
+		}
+	}
+	if (cb->args[1]) {
+		cb->args[1] = 0;
+		goto restart;
+	}
+out:
+	rcu_read_unlock();
+	return skb->len;
+}
+
+static int
+nfnl_cthelper_get(struct sock *nfnl, struct sk_buff *skb,
+		  const struct nlmsghdr *nlh, const struct nlattr * const tb[])
+{
+	int ret = -ENOENT, i;
+	struct nf_conntrack_helper *cur;
+	struct hlist_node *n;
+	struct sk_buff *skb2;
+	char *helper_name = NULL;
+	struct nf_conntrack_tuple tuple;
+	bool tuple_set = false;
+
+	if (nlh->nlmsg_flags & NLM_F_DUMP) {
+		struct netlink_dump_control c = {
+			.dump = nfnl_cthelper_dump_table,
+		};
+		return netlink_dump_start(nfnl, skb, nlh, &c);
+	}
+
+	if (tb[NFCTH_NAME])
+		helper_name = nla_data(tb[NFCTH_NAME]);
+
+	if (tb[NFCTH_TUPLE]) {
+		ret = nfnl_cthelper_parse_tuple(&tuple, tb[NFCTH_TUPLE]);
+		if (ret < 0)
+			return ret;
+
+		tuple_set = true;
+	}
+
+	for (i = 0; i < nf_ct_helper_hsize; i++) {
+		hlist_for_each_entry_rcu(cur, n, &nf_ct_helper_hash[i], hnode) {
+
+			/* skip non-userspace conntrack helpers. */
+			if (!(cur->flags & NF_CT_HELPER_F_USERSPACE))
+				continue;
+
+			if (helper_name && strncmp(cur->name, helper_name,
+						NF_CT_HELPER_NAME_LEN) != 0) {
+				continue;
+			}
+			if (tuple_set &&
+			    (tuple.src.l3num != cur->tuple.src.l3num ||
+			     tuple.dst.protonum != cur->tuple.dst.protonum))
+				continue;
+
+			skb2 = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
+			if (skb2 == NULL) {
+				ret = -ENOMEM;
+				break;
+			}
+
+			ret = nfnl_cthelper_fill_info(skb2, NETLINK_CB(skb).pid,
+						nlh->nlmsg_seq,
+						NFNL_MSG_TYPE(nlh->nlmsg_type),
+						NFNL_MSG_CTHELPER_NEW, cur);
+			if (ret <= 0) {
+				kfree_skb(skb2);
+				break;
+			}
+
+			ret = netlink_unicast(nfnl, skb2, NETLINK_CB(skb).pid,
+						MSG_DONTWAIT);
+			if (ret > 0)
+				ret = 0;
+
+			/* this avoids a loop in nfnetlink. */
+			return ret == -EAGAIN ? -ENOBUFS : ret;
+		}
+	}
+	return ret;
+}
+
+static int
+nfnl_cthelper_del(struct sock *nfnl, struct sk_buff *skb,
+	     const struct nlmsghdr *nlh, const struct nlattr * const tb[])
+{
+	char *helper_name = NULL;
+	struct nf_conntrack_helper *cur;
+	struct hlist_node *n, *tmp;
+	struct nf_conntrack_tuple tuple;
+	bool tuple_set = false, found = false;
+	int i, j = 0, ret;
+
+	if (tb[NFCTH_NAME])
+		helper_name = nla_data(tb[NFCTH_NAME]);
+
+	if (tb[NFCTH_TUPLE]) {
+		ret = nfnl_cthelper_parse_tuple(&tuple, tb[NFCTH_TUPLE]);
+		if (ret < 0)
+			return ret;
+
+		tuple_set = true;
+	}
+
+	for (i = 0; i < nf_ct_helper_hsize; i++) {
+		hlist_for_each_entry_safe(cur, n, tmp, &nf_ct_helper_hash[i],
+								hnode) {
+			/* skip non-userspace conntrack helpers. */
+			if (!(cur->flags & NF_CT_HELPER_F_USERSPACE))
+				continue;
+
+			j++;
+
+			if (helper_name && strncmp(cur->name, helper_name,
+						NF_CT_HELPER_NAME_LEN) != 0) {
+				continue;
+			}
+			if (tuple_set &&
+			    (tuple.src.l3num != cur->tuple.src.l3num ||
+			     tuple.dst.protonum != cur->tuple.dst.protonum))
+				continue;
+
+			found = true;
+			nf_conntrack_helper_unregister(cur);
+		}
+	}
+	/* Make sure we return success if we flush and there is no helpers */
+	return (found || j == 0) ? 0 : -ENOENT;
+}
+
+static const struct nla_policy nfnl_cthelper_policy[NFCTH_MAX+1] = {
+	[NFCTH_NAME] = { .type = NLA_NUL_STRING,
+			 .len = NF_CT_HELPER_NAME_LEN-1 },
+	[NFCTH_QUEUE_NUM] = { .type = NLA_U32, },
+};
+
+static const struct nfnl_callback nfnl_cthelper_cb[NFNL_MSG_CTHELPER_MAX] = {
+	[NFNL_MSG_CTHELPER_NEW]		= { .call = nfnl_cthelper_new,
+					    .attr_count = NFCTH_MAX,
+					    .policy = nfnl_cthelper_policy },
+	[NFNL_MSG_CTHELPER_GET]		= { .call = nfnl_cthelper_get,
+					    .attr_count = NFCTH_MAX,
+					    .policy = nfnl_cthelper_policy },
+	[NFNL_MSG_CTHELPER_DEL]		= { .call = nfnl_cthelper_del,
+					    .attr_count = NFCTH_MAX,
+					    .policy = nfnl_cthelper_policy },
+};
+
+static const struct nfnetlink_subsystem nfnl_cthelper_subsys = {
+	.name				= "cthelper",
+	.subsys_id			= NFNL_SUBSYS_CTHELPER,
+	.cb_count			= NFNL_MSG_CTHELPER_MAX,
+	.cb				= nfnl_cthelper_cb,
+};
+
+MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTHELPER);
+
+static int __init nfnl_cthelper_init(void)
+{
+	int ret;
+
+	ret = nfnetlink_subsys_register(&nfnl_cthelper_subsys);
+	if (ret < 0) {
+		pr_err("nfnl_cthelper: cannot register with nfnetlink.\n");
+		goto err_out;
+	}
+	return 0;
+err_out:
+	return ret;
+}
+
+static void __exit nfnl_cthelper_exit(void)
+{
+	struct nf_conntrack_helper *cur;
+	struct hlist_node *n, *tmp;
+	int i;
+
+	nfnetlink_subsys_unregister(&nfnl_cthelper_subsys);
+
+	for (i=0; i<nf_ct_helper_hsize; i++) {
+		hlist_for_each_entry_safe(cur, n, tmp, &nf_ct_helper_hash[i],
+									hnode) {
+			/* skip non-userspace conntrack helpers. */
+			if (!(cur->flags & NF_CT_HELPER_F_USERSPACE))
+				continue;
+
+			nf_conntrack_helper_unregister(cur);
+		}
+	}
+}
+
+module_init(nfnl_cthelper_init);
+module_exit(nfnl_cthelper_exit);

net/netfilter/nfnetlink_queue.c

@@ -30,6 +30,7 @@
 #include <linux/list.h>
 #include <net/sock.h>
 #include <net/netfilter/nf_queue.h>
+#include <net/netfilter/nf_conntrack.h>
 
 #include <linux/atomic.h>
 
@@ -233,6 +234,9 @@ nfqnl_build_packet_message(struct nfqnl_instance *queue,
 	struct sk_buff *entskb = entry->skb;
 	struct net_device *indev;
 	struct net_device *outdev;
+	struct nfq_ct_hook *nfq_ct;
+	struct nf_conn *ct = NULL;
+	enum ip_conntrack_info uninitialized_var(ctinfo);
 
 	size =    NLMSG_SPACE(sizeof(struct nfgenmsg))
 		+ nla_total_size(sizeof(struct nfqnl_msg_packet_hdr))
@@ -266,6 +270,17 @@ nfqnl_build_packet_message(struct nfqnl_instance *queue,
 		break;
 	}
 
+	/* rcu_read_lock()ed by __nf_queue already. */
+	nfq_ct = rcu_dereference(nfq_ct_hook);
+	if (nfq_ct != NULL && (queue->flags & NFQA_CFG_F_CONNTRACK)) {
+		ct = nf_ct_get(entskb, &ctinfo);
+		if (ct) {
+			if (!nf_ct_is_untracked(ct))
+				size += nfq_ct->build_size(ct);
+			else
+				ct = NULL;
+		}
+	}
 
 	skb = alloc_skb(size, GFP_ATOMIC);
 	if (!skb)
@@ -389,6 +404,24 @@ nfqnl_build_packet_message(struct nfqnl_instance *queue,
 			BUG();
 	}
 
+	if (ct) {
+		struct nlattr *nest_parms;
+		u_int32_t tmp;
+
+		nest_parms = nla_nest_start(skb, NFQA_CT | NLA_F_NESTED);
+		if (!nest_parms)
+			goto nla_put_failure;
+
+		if (nfq_ct->build(skb, ct) < 0)
+			goto nla_put_failure;
+
+		nla_nest_end(skb, nest_parms);
+
+		tmp = ctinfo;
+		if (nla_put_u32(skb, NFQA_CT_INFO, htonl(ctinfo)))
+			goto nla_put_failure;
+	}
+
 	nlh->nlmsg_len = skb->tail - old_tail;
 	return skb;
 
@@ -469,12 +502,10 @@ nfqnl_enqueue_packet(struct nf_queue_entry *entry, unsigned int queuenum)
 }
 
 static int
-nfqnl_mangle(void *data, int data_len, struct nf_queue_entry *e)
+nfqnl_mangle(void *data, int data_len, struct nf_queue_entry *e, int diff)
 {
 	struct sk_buff *nskb;
-	int diff;
 
-	diff = data_len - e->skb->len;
 	if (diff < 0) {
 		if (pskb_trim(e->skb, data_len))
 			return -ENOMEM;
@@ -632,6 +663,7 @@ static const struct nla_policy nfqa_verdict_policy[NFQA_MAX+1] = {
 	[NFQA_VERDICT_HDR]	= { .len = sizeof(struct nfqnl_msg_verdict_hdr) },
 	[NFQA_MARK]		= { .type = NLA_U32 },
 	[NFQA_PAYLOAD]		= { .type = NLA_UNSPEC },
+	[NFQA_CT]		= { .type = NLA_UNSPEC },
 };
 
 static const struct nla_policy nfqa_verdict_batch_policy[NFQA_MAX+1] = {
@@ -732,6 +764,9 @@ nfqnl_recv_verdict(struct sock *ctnl, struct sk_buff *skb,
 	struct nfqnl_instance *queue;
 	unsigned int verdict;
 	struct nf_queue_entry *entry;
+	struct nfq_ct_hook *nfq_ct;
+	enum ip_conntrack_info uninitialized_var(ctinfo);
+	struct nf_conn *ct = NULL;
 
 	queue = instance_lookup(queue_num);
 	if (!queue)
@@ -750,11 +785,27 @@ nfqnl_recv_verdict(struct sock *ctnl, struct sk_buff *skb,
 	if (entry == NULL)
 		return -ENOENT;
 
+	rcu_read_lock();
+	nfq_ct = rcu_dereference(nfq_ct_hook);
+	if (nfq_ct != NULL &&
+	    (queue->flags & NFQA_CFG_F_CONNTRACK) && nfqa[NFQA_CT]) {
+		ct = nf_ct_get(entry->skb, &ctinfo);
+		if (ct && !nf_ct_is_untracked(ct))
+			nfq_ct->parse(nfqa[NFQA_CT], ct);
+	}
+
 	if (nfqa[NFQA_PAYLOAD]) {
+		u16 payload_len = nla_len(nfqa[NFQA_PAYLOAD]);
+		int diff = payload_len - entry->skb->len;
+
 		if (nfqnl_mangle(nla_data(nfqa[NFQA_PAYLOAD]),
-				 nla_len(nfqa[NFQA_PAYLOAD]), entry) < 0)
+				 payload_len, entry, diff) < 0)
 			verdict = NF_DROP;
+
+		if (ct && (ct->status & IPS_NAT_MASK) && diff)
+			nfq_ct->seq_adjust(skb, ct, ctinfo, diff);
 	}
+	rcu_read_unlock();
 
 	if (nfqa[NFQA_MARK])
 		entry->skb->mark = ntohl(nla_get_be32(nfqa[NFQA_MARK]));

net/netfilter/xt_CT.c

@@ -112,6 +112,8 @@ static int xt_ct_tg_check_v0(const struct xt_tgchk_param *par)
 		goto err3;
 
 	if (info->helper[0]) {
+		struct nf_conntrack_helper *helper;
+
 		ret = -ENOENT;
 		proto = xt_ct_find_proto(par);
 		if (!proto) {
@@ -120,19 +122,21 @@ static int xt_ct_tg_check_v0(const struct xt_tgchk_param *par)
 			goto err3;
 		}
 
-		ret = -ENOMEM;
-		help = nf_ct_helper_ext_add(ct, GFP_KERNEL);
-		if (help == NULL)
-			goto err3;
-
 		ret = -ENOENT;
-		help->helper = nf_conntrack_helper_try_module_get(info->helper,
+		helper = nf_conntrack_helper_try_module_get(info->helper,
 							    par->family,
 							    proto);
-		if (help->helper == NULL) {
+		if (helper == NULL) {
 			pr_info("No such helper \"%s\"\n", info->helper);
 			goto err3;
 		}
+
+		ret = -ENOMEM;
+		help = nf_ct_helper_ext_add(ct, helper, GFP_KERNEL);
+		if (help == NULL)
+			goto err3;
+
+		help->helper = helper;
 	}
 
 	__set_bit(IPS_TEMPLATE_BIT, &ct->status);
@@ -202,6 +206,8 @@ static int xt_ct_tg_check_v1(const struct xt_tgchk_param *par)
 		goto err3;
 
 	if (info->helper[0]) {
+		struct nf_conntrack_helper *helper;
+
 		ret = -ENOENT;
 		proto = xt_ct_find_proto(par);
 		if (!proto) {
@@ -210,19 +216,21 @@ static int xt_ct_tg_check_v1(const struct xt_tgchk_param *par)
 			goto err3;
 		}
 
-		ret = -ENOMEM;
-		help = nf_ct_helper_ext_add(ct, GFP_KERNEL);
-		if (help == NULL)
-			goto err3;
-
 		ret = -ENOENT;
-		help->helper = nf_conntrack_helper_try_module_get(info->helper,
+		helper = nf_conntrack_helper_try_module_get(info->helper,
 							    par->family,
 							    proto);
-		if (help->helper == NULL) {
+		if (helper == NULL) {
 			pr_info("No such helper \"%s\"\n", info->helper);
 			goto err3;
 		}
+
+		ret = -ENOMEM;
+		help = nf_ct_helper_ext_add(ct, helper, GFP_KERNEL);
+		if (help == NULL)
+			goto err3;
+
+		help->helper = helper;
 	}
 
 #ifdef CONFIG_NF_CONNTRACK_TIMEOUT