netfilter: h323: merge nat hook pointers into one

sparse complains about incorrect rcu usage.

Code uses the correct rcu access primitives, but the function pointers
lack rcu annotations.

Collapse all of them into a single structure, then annotate the pointer.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

3 files changed, 169 insertions, 242 deletions

diff --git a/include/linux/netfilter/nf_conntrack_h323.h b/include/linux/netfilter/nf_conntrack_h323.h
index 4561ec0fcea4..9e937f64a1ad 100644
--- a/include/linux/netfilter/nf_conntrack_h323.h
+++ b/include/linux/netfilter/nf_conntrack_h323.h
@@ -38,60 +38,63 @@ void nf_conntrack_h245_expect(struct nf_conn *new,
 			      struct nf_conntrack_expect *this);
 void nf_conntrack_q931_expect(struct nf_conn *new,
 			      struct nf_conntrack_expect *this);
-extern int (*set_h245_addr_hook) (struct sk_buff *skb, unsigned int protoff,
-				  unsigned char **data, int dataoff,
-				  H245_TransportAddress *taddr,
-				  union nf_inet_addr *addr,
-				  __be16 port);
-extern int (*set_h225_addr_hook) (struct sk_buff *skb, unsigned int protoff,
-				  unsigned char **data, int dataoff,
-				  TransportAddress *taddr,
-				  union nf_inet_addr *addr,
-				  __be16 port);
-extern int (*set_sig_addr_hook) (struct sk_buff *skb,
-				 struct nf_conn *ct,
-				 enum ip_conntrack_info ctinfo,
-				 unsigned int protoff, unsigned char **data,
-				 TransportAddress *taddr, int count);
-extern int (*set_ras_addr_hook) (struct sk_buff *skb,
-				 struct nf_conn *ct,
-				 enum ip_conntrack_info ctinfo,
-				 unsigned int protoff, unsigned char **data,
-				 TransportAddress *taddr, int count);
-extern int (*nat_rtp_rtcp_hook) (struct sk_buff *skb,
-				 struct nf_conn *ct,
-				 enum ip_conntrack_info ctinfo,
-				 unsigned int protoff, unsigned char **data,
-				 int dataoff,
-				 H245_TransportAddress *taddr,
-				 __be16 port, __be16 rtp_port,
-				 struct nf_conntrack_expect *rtp_exp,
-				 struct nf_conntrack_expect *rtcp_exp);
-extern int (*nat_t120_hook) (struct sk_buff *skb, struct nf_conn *ct,
-			     enum ip_conntrack_info ctinfo,
-			     unsigned int protoff,
+
+struct nfct_h323_nat_hooks {
+	int (*set_h245_addr)(struct sk_buff *skb, unsigned int protoff,
 			     unsigned char **data, int dataoff,
-			     H245_TransportAddress *taddr, __be16 port,
-			     struct nf_conntrack_expect *exp);
-extern int (*nat_h245_hook) (struct sk_buff *skb, struct nf_conn *ct,
-			     enum ip_conntrack_info ctinfo,
-			     unsigned int protoff,
+			     H245_TransportAddress *taddr,
+			     union nf_inet_addr *addr, __be16 port);
+	int (*set_h225_addr)(struct sk_buff *skb, unsigned int protoff,
 			     unsigned char **data, int dataoff,
-			     TransportAddress *taddr, __be16 port,
-			     struct nf_conntrack_expect *exp);
-extern int (*nat_callforwarding_hook) (struct sk_buff *skb,
-				       struct nf_conn *ct,
-				       enum ip_conntrack_info ctinfo,
-				       unsigned int protoff,
-				       unsigned char **data, int dataoff,
-				       TransportAddress *taddr,
-				       __be16 port,
-				       struct nf_conntrack_expect *exp);
-extern int (*nat_q931_hook) (struct sk_buff *skb, struct nf_conn *ct,
-			     enum ip_conntrack_info ctinfo,
-			     unsigned int protoff,
-			     unsigned char **data, TransportAddress *taddr,
-			     int idx, __be16 port,
-			     struct nf_conntrack_expect *exp);
+			     TransportAddress *taddr,
+			     union nf_inet_addr *addr, __be16 port);
+	int (*set_sig_addr)(struct sk_buff *skb,
+			    struct nf_conn *ct,
+			    enum ip_conntrack_info ctinfo,
+			    unsigned int protoff, unsigned char **data,
+			    TransportAddress *taddr, int count);
+	int (*set_ras_addr)(struct sk_buff *skb,
+			    struct nf_conn *ct,
+			    enum ip_conntrack_info ctinfo,
+			    unsigned int protoff, unsigned char **data,
+			    TransportAddress *taddr, int count);
+	int (*nat_rtp_rtcp)(struct sk_buff *skb,
+			    struct nf_conn *ct,
+			    enum ip_conntrack_info ctinfo,
+			    unsigned int protoff,
+			    unsigned char **data, int dataoff,
+			    H245_TransportAddress *taddr,
+			    __be16 port, __be16 rtp_port,
+			    struct nf_conntrack_expect *rtp_exp,
+			    struct nf_conntrack_expect *rtcp_exp);
+	int (*nat_t120)(struct sk_buff *skb,
+			struct nf_conn *ct,
+			enum ip_conntrack_info ctinfo,
+			unsigned int protoff,
+			unsigned char **data, int dataoff,
+			H245_TransportAddress *taddr, __be16 port,
+			struct nf_conntrack_expect *exp);
+	int (*nat_h245)(struct sk_buff *skb,
+			struct nf_conn *ct,
+			enum ip_conntrack_info ctinfo,
+			unsigned int protoff,
+			unsigned char **data, int dataoff,
+			TransportAddress *taddr, __be16 port,
+			struct nf_conntrack_expect *exp);
+	int (*nat_callforwarding)(struct sk_buff *skb,
+				  struct nf_conn *ct,
+				  enum ip_conntrack_info ctinfo,
+				  unsigned int protoff,
+				  unsigned char **data, int dataoff,
+				  TransportAddress *taddr, __be16 port,
+				  struct nf_conntrack_expect *exp);
+	int (*nat_q931)(struct sk_buff *skb,
+			struct nf_conn *ct,
+			enum ip_conntrack_info ctinfo,
+			unsigned int protoff,
+			unsigned char **data, TransportAddress *taddr, int idx,
+			__be16 port, struct nf_conntrack_expect *exp);
+};
+extern const struct nfct_h323_nat_hooks __rcu *nfct_h323_nat_hook;
 
 #endif
diff --git a/net/ipv4/netfilter/nf_nat_h323.c b/net/ipv4/netfilter/nf_nat_h323.c
index 76a411ae9fe6..a334f0dcc2d0 100644
--- a/net/ipv4/netfilter/nf_nat_h323.c
+++ b/net/ipv4/netfilter/nf_nat_h323.c
@@ -579,28 +579,22 @@ static struct nf_ct_helper_expectfn callforwarding_nat = {
 	.expectfn	= ip_nat_callforwarding_expect,
 };
 
+static const struct nfct_h323_nat_hooks nathooks = {
+	.set_h245_addr = set_h245_addr,
+	.set_h225_addr = set_h225_addr,
+	.set_sig_addr = set_sig_addr,
+	.set_ras_addr = set_ras_addr,
+	.nat_rtp_rtcp = nat_rtp_rtcp,
+	.nat_t120 = nat_t120,
+	.nat_h245 = nat_h245,
+	.nat_callforwarding = nat_callforwarding,
+	.nat_q931 = nat_q931,
+};
+
 /****************************************************************************/
 static int __init nf_nat_h323_init(void)
 {
-	BUG_ON(set_h245_addr_hook != NULL);
-	BUG_ON(set_h225_addr_hook != NULL);
-	BUG_ON(set_sig_addr_hook != NULL);
-	BUG_ON(set_ras_addr_hook != NULL);
-	BUG_ON(nat_rtp_rtcp_hook != NULL);
-	BUG_ON(nat_t120_hook != NULL);
-	BUG_ON(nat_h245_hook != NULL);
-	BUG_ON(nat_callforwarding_hook != NULL);
-	BUG_ON(nat_q931_hook != NULL);
-
-	RCU_INIT_POINTER(set_h245_addr_hook, set_h245_addr);
-	RCU_INIT_POINTER(set_h225_addr_hook, set_h225_addr);
-	RCU_INIT_POINTER(set_sig_addr_hook, set_sig_addr);
-	RCU_INIT_POINTER(set_ras_addr_hook, set_ras_addr);
-	RCU_INIT_POINTER(nat_rtp_rtcp_hook, nat_rtp_rtcp);
-	RCU_INIT_POINTER(nat_t120_hook, nat_t120);
-	RCU_INIT_POINTER(nat_h245_hook, nat_h245);
-	RCU_INIT_POINTER(nat_callforwarding_hook, nat_callforwarding);
-	RCU_INIT_POINTER(nat_q931_hook, nat_q931);
+	RCU_INIT_POINTER(nfct_h323_nat_hook, &nathooks);
 	nf_ct_helper_expectfn_register(&q931_nat);
 	nf_ct_helper_expectfn_register(&callforwarding_nat);
 	return 0;
@@ -609,15 +603,7 @@ static int __init nf_nat_h323_init(void)
 /****************************************************************************/
 static void __exit nf_nat_h323_fini(void)
 {
-	RCU_INIT_POINTER(set_h245_addr_hook, NULL);
-	RCU_INIT_POINTER(set_h225_addr_hook, NULL);
-	RCU_INIT_POINTER(set_sig_addr_hook, NULL);
-	RCU_INIT_POINTER(set_ras_addr_hook, NULL);
-	RCU_INIT_POINTER(nat_rtp_rtcp_hook, NULL);
-	RCU_INIT_POINTER(nat_t120_hook, NULL);
-	RCU_INIT_POINTER(nat_h245_hook, NULL);
-	RCU_INIT_POINTER(nat_callforwarding_hook, NULL);
-	RCU_INIT_POINTER(nat_q931_hook, NULL);
+	RCU_INIT_POINTER(nfct_h323_nat_hook, NULL);
 	nf_ct_helper_expectfn_unregister(&q931_nat);
 	nf_ct_helper_expectfn_unregister(&callforwarding_nat);
 	synchronize_rcu();
diff --git a/net/netfilter/nf_conntrack_h323_main.c b/net/netfilter/nf_conntrack_h323_main.c
index 2eb31ffb3d14..bb76305bb7ff 100644
--- a/net/netfilter/nf_conntrack_h323_main.c
+++ b/net/netfilter/nf_conntrack_h323_main.c
@@ -49,64 +49,8 @@ MODULE_PARM_DESC(callforward_filter, "only create call forwarding expectations "
 				     "if both endpoints are on different sides "
 				     "(determined by routing information)");
 
-/* Hooks for NAT */
-int (*set_h245_addr_hook) (struct sk_buff *skb, unsigned int protoff,
-			   unsigned char **data, int dataoff,
-			   H245_TransportAddress *taddr,
-			   union nf_inet_addr *addr, __be16 port)
-			   __read_mostly;
-int (*set_h225_addr_hook) (struct sk_buff *skb, unsigned int protoff,
-			   unsigned char **data, int dataoff,
-			   TransportAddress *taddr,
-			   union nf_inet_addr *addr, __be16 port)
-			   __read_mostly;
-int (*set_sig_addr_hook) (struct sk_buff *skb,
-			  struct nf_conn *ct,
-			  enum ip_conntrack_info ctinfo,
-			  unsigned int protoff, unsigned char **data,
-			  TransportAddress *taddr, int count) __read_mostly;
-int (*set_ras_addr_hook) (struct sk_buff *skb,
-			  struct nf_conn *ct,
-			  enum ip_conntrack_info ctinfo,
-			  unsigned int protoff, unsigned char **data,
-			  TransportAddress *taddr, int count) __read_mostly;
-int (*nat_rtp_rtcp_hook) (struct sk_buff *skb,
-			  struct nf_conn *ct,
-			  enum ip_conntrack_info ctinfo,
-			  unsigned int protoff,
-			  unsigned char **data, int dataoff,
-			  H245_TransportAddress *taddr,
-			  __be16 port, __be16 rtp_port,
-			  struct nf_conntrack_expect *rtp_exp,
-			  struct nf_conntrack_expect *rtcp_exp) __read_mostly;
-int (*nat_t120_hook) (struct sk_buff *skb,
-		      struct nf_conn *ct,
-		      enum ip_conntrack_info ctinfo,
-		      unsigned int protoff,
-		      unsigned char **data, int dataoff,
-		      H245_TransportAddress *taddr, __be16 port,
-		      struct nf_conntrack_expect *exp) __read_mostly;
-int (*nat_h245_hook) (struct sk_buff *skb,
-		      struct nf_conn *ct,
-		      enum ip_conntrack_info ctinfo,
-		      unsigned int protoff,
-		      unsigned char **data, int dataoff,
-		      TransportAddress *taddr, __be16 port,
-		      struct nf_conntrack_expect *exp) __read_mostly;
-int (*nat_callforwarding_hook) (struct sk_buff *skb,
-				struct nf_conn *ct,
-				enum ip_conntrack_info ctinfo,
-				unsigned int protoff,
-				unsigned char **data, int dataoff,
-				TransportAddress *taddr, __be16 port,
-				struct nf_conntrack_expect *exp) __read_mostly;
-int (*nat_q931_hook) (struct sk_buff *skb,
-		      struct nf_conn *ct,
-		      enum ip_conntrack_info ctinfo,
-		      unsigned int protoff,
-		      unsigned char **data, TransportAddress *taddr, int idx,
-		      __be16 port, struct nf_conntrack_expect *exp)
-		      __read_mostly;
+const struct nfct_h323_nat_hooks __rcu *nfct_h323_nat_hook __read_mostly;
+EXPORT_SYMBOL_GPL(nfct_h323_nat_hook);
 
 static DEFINE_SPINLOCK(nf_h323_lock);
 static char *h323_buffer;
@@ -259,6 +203,7 @@ static int expect_rtp_rtcp(struct sk_buff *skb, struct nf_conn *ct,
 			   unsigned char **data, int dataoff,
 			   H245_TransportAddress *taddr)
 {
+	const struct nfct_h323_nat_hooks *nathook;
 	int dir = CTINFO2DIR(ctinfo);
 	int ret = 0;
 	__be16 port;
@@ -266,7 +211,6 @@ static int expect_rtp_rtcp(struct sk_buff *skb, struct nf_conn *ct,
 	union nf_inet_addr addr;
 	struct nf_conntrack_expect *rtp_exp;
 	struct nf_conntrack_expect *rtcp_exp;
-	typeof(nat_rtp_rtcp_hook) nat_rtp_rtcp;
 
 	/* Read RTP or RTCP address */
 	if (!get_h245_addr(ct, *data, taddr, &addr, &port) ||
@@ -296,15 +240,16 @@ static int expect_rtp_rtcp(struct sk_buff *skb, struct nf_conn *ct,
 			  &ct->tuplehash[!dir].tuple.dst.u3,
 			  IPPROTO_UDP, NULL, &rtcp_port);
 
+	nathook = rcu_dereference(nfct_h323_nat_hook);
 	if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 		   &ct->tuplehash[!dir].tuple.dst.u3,
 		   sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
-		   (nat_rtp_rtcp = rcu_dereference(nat_rtp_rtcp_hook)) &&
+		   nathook &&
 		   nf_ct_l3num(ct) == NFPROTO_IPV4 &&
 		   ct->status & IPS_NAT_MASK) {
 		/* NAT needed */
-		ret = nat_rtp_rtcp(skb, ct, ctinfo, protoff, data, dataoff,
-				   taddr, port, rtp_port, rtp_exp, rtcp_exp);
+		ret = nathook->nat_rtp_rtcp(skb, ct, ctinfo, protoff, data, dataoff,
+					    taddr, port, rtp_port, rtp_exp, rtcp_exp);
 	} else {		/* Conntrack only */
 		if (nf_ct_expect_related(rtp_exp, 0) == 0) {
 			if (nf_ct_expect_related(rtcp_exp, 0) == 0) {
@@ -333,12 +278,12 @@ static int expect_t120(struct sk_buff *skb,
 		       unsigned char **data, int dataoff,
 		       H245_TransportAddress *taddr)
 {
+	const struct nfct_h323_nat_hooks *nathook;
 	int dir = CTINFO2DIR(ctinfo);
 	int ret = 0;
 	__be16 port;
 	union nf_inet_addr addr;
 	struct nf_conntrack_expect *exp;
-	typeof(nat_t120_hook) nat_t120;
 
 	/* Read T.120 address */
 	if (!get_h245_addr(ct, *data, taddr, &addr, &port) ||
@@ -355,15 +300,16 @@ static int expect_t120(struct sk_buff *skb,
 			  IPPROTO_TCP, NULL, &port);
 	exp->flags = NF_CT_EXPECT_PERMANENT;	/* Accept multiple channels */
 
+	nathook = rcu_dereference(nfct_h323_nat_hook);
 	if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 		   &ct->tuplehash[!dir].tuple.dst.u3,
 		   sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
-	    (nat_t120 = rcu_dereference(nat_t120_hook)) &&
+	    nathook &&
 	    nf_ct_l3num(ct) == NFPROTO_IPV4 &&
 	    ct->status & IPS_NAT_MASK) {
 		/* NAT needed */
-		ret = nat_t120(skb, ct, ctinfo, protoff, data, dataoff, taddr,
-			       port, exp);
+		ret = nathook->nat_t120(skb, ct, ctinfo, protoff, data,
+					dataoff, taddr, port, exp);
 	} else {		/* Conntrack only */
 		if (nf_ct_expect_related(exp, 0) == 0) {
 			pr_debug("nf_ct_h323: expect T.120 ");
@@ -664,18 +610,19 @@ int get_h225_addr(struct nf_conn *ct, unsigned char *data,
 
 	return 1;
 }
+EXPORT_SYMBOL_GPL(get_h225_addr);
 
 static int expect_h245(struct sk_buff *skb, struct nf_conn *ct,
 		       enum ip_conntrack_info ctinfo,
 		       unsigned int protoff, unsigned char **data, int dataoff,
 		       TransportAddress *taddr)
 {
+	const struct nfct_h323_nat_hooks *nathook;
 	int dir = CTINFO2DIR(ctinfo);
 	int ret = 0;
 	__be16 port;
 	union nf_inet_addr addr;
 	struct nf_conntrack_expect *exp;
-	typeof(nat_h245_hook) nat_h245;
 
 	/* Read h245Address */
 	if (!get_h225_addr(ct, *data, taddr, &addr, &port) ||
@@ -692,15 +639,16 @@ static int expect_h245(struct sk_buff *skb, struct nf_conn *ct,
 			  IPPROTO_TCP, NULL, &port);
 	exp->helper = &nf_conntrack_helper_h245;
 
+	nathook = rcu_dereference(nfct_h323_nat_hook);
 	if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 		   &ct->tuplehash[!dir].tuple.dst.u3,
 		   sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
-	    (nat_h245 = rcu_dereference(nat_h245_hook)) &&
+	    nathook &&
 	    nf_ct_l3num(ct) == NFPROTO_IPV4 &&
 	    ct->status & IPS_NAT_MASK) {
 		/* NAT needed */
-		ret = nat_h245(skb, ct, ctinfo, protoff, data, dataoff, taddr,
-			       port, exp);
+		ret = nathook->nat_h245(skb, ct, ctinfo, protoff, data,
+					dataoff, taddr, port, exp);
 	} else {		/* Conntrack only */
 		if (nf_ct_expect_related(exp, 0) == 0) {
 			pr_debug("nf_ct_q931: expect H.245 ");
@@ -785,13 +733,13 @@ static int expect_callforwarding(struct sk_buff *skb,
 				 unsigned char **data, int dataoff,
 				 TransportAddress *taddr)
 {
+	const struct nfct_h323_nat_hooks *nathook;
 	int dir = CTINFO2DIR(ctinfo);
 	int ret = 0;
 	__be16 port;
 	union nf_inet_addr addr;
 	struct nf_conntrack_expect *exp;
 	struct net *net = nf_ct_net(ct);
-	typeof(nat_callforwarding_hook) nat_callforwarding;
 
 	/* Read alternativeAddress */
 	if (!get_h225_addr(ct, *data, taddr, &addr, &port) || port == 0)
@@ -815,16 +763,17 @@ static int expect_callforwarding(struct sk_buff *skb,
 			  IPPROTO_TCP, NULL, &port);
 	exp->helper = nf_conntrack_helper_q931;
 
+	nathook = rcu_dereference(nfct_h323_nat_hook);
 	if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 		   &ct->tuplehash[!dir].tuple.dst.u3,
 		   sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
-	    (nat_callforwarding = rcu_dereference(nat_callforwarding_hook)) &&
+	    nathook &&
 	    nf_ct_l3num(ct) == NFPROTO_IPV4 &&
 	    ct->status & IPS_NAT_MASK) {
 		/* Need NAT */
-		ret = nat_callforwarding(skb, ct, ctinfo,
-					 protoff, data, dataoff,
-					 taddr, port, exp);
+		ret = nathook->nat_callforwarding(skb, ct, ctinfo,
+						  protoff, data, dataoff,
+						  taddr, port, exp);
 	} else {		/* Conntrack only */
 		if (nf_ct_expect_related(exp, 0) == 0) {
 			pr_debug("nf_ct_q931: expect Call Forwarding ");
@@ -844,12 +793,12 @@ static int process_setup(struct sk_buff *skb, struct nf_conn *ct,
 			 unsigned char **data, int dataoff,
 			 Setup_UUIE *setup)
 {
+	const struct nfct_h323_nat_hooks *nathook;
 	int dir = CTINFO2DIR(ctinfo);
 	int ret;
 	int i;
 	__be16 port;
 	union nf_inet_addr addr;
-	typeof(set_h225_addr_hook) set_h225_addr;
 
 	pr_debug("nf_ct_q931: Setup\n");
 
@@ -860,9 +809,9 @@ static int process_setup(struct sk_buff *skb, struct nf_conn *ct,
 			return -1;
 	}
 
-	set_h225_addr = rcu_dereference(set_h225_addr_hook);
+	nathook = rcu_dereference(nfct_h323_nat_hook);
 	if ((setup->options & eSetup_UUIE_destCallSignalAddress) &&
-	    (set_h225_addr) && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
+	    nathook && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
 	    ct->status & IPS_NAT_MASK &&
 	    get_h225_addr(ct, *data, &setup->destCallSignalAddress,
 			  &addr, &port) &&
@@ -870,16 +819,16 @@ static int process_setup(struct sk_buff *skb, struct nf_conn *ct,
 		pr_debug("nf_ct_q931: set destCallSignalAddress %pI6:%hu->%pI6:%hu\n",
 			 &addr, ntohs(port), &ct->tuplehash[!dir].tuple.src.u3,
 			 ntohs(ct->tuplehash[!dir].tuple.src.u.tcp.port));
-		ret = set_h225_addr(skb, protoff, data, dataoff,
-				    &setup->destCallSignalAddress,
-				    &ct->tuplehash[!dir].tuple.src.u3,
-				    ct->tuplehash[!dir].tuple.src.u.tcp.port);
+		ret = nathook->set_h225_addr(skb, protoff, data, dataoff,
+					     &setup->destCallSignalAddress,
+					     &ct->tuplehash[!dir].tuple.src.u3,
+					     ct->tuplehash[!dir].tuple.src.u.tcp.port);
 		if (ret < 0)
 			return -1;
 	}
 
 	if ((setup->options & eSetup_UUIE_sourceCallSignalAddress) &&
-	    (set_h225_addr) && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
+	    nathook && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
 	    ct->status & IPS_NAT_MASK &&
 	    get_h225_addr(ct, *data, &setup->sourceCallSignalAddress,
 			  &addr, &port) &&
@@ -887,10 +836,10 @@ static int process_setup(struct sk_buff *skb, struct nf_conn *ct,
 		pr_debug("nf_ct_q931: set sourceCallSignalAddress %pI6:%hu->%pI6:%hu\n",
 			 &addr, ntohs(port), &ct->tuplehash[!dir].tuple.dst.u3,
 			 ntohs(ct->tuplehash[!dir].tuple.dst.u.tcp.port));
-		ret = set_h225_addr(skb, protoff, data, dataoff,
-				    &setup->sourceCallSignalAddress,
-				    &ct->tuplehash[!dir].tuple.dst.u3,
-				    ct->tuplehash[!dir].tuple.dst.u.tcp.port);
+		ret = nathook->set_h225_addr(skb, protoff, data, dataoff,
+					     &setup->sourceCallSignalAddress,
+					     &ct->tuplehash[!dir].tuple.dst.u3,
+					     ct->tuplehash[!dir].tuple.dst.u.tcp.port);
 		if (ret < 0)
 			return -1;
 	}
@@ -1249,13 +1198,13 @@ static int expect_q931(struct sk_buff *skb, struct nf_conn *ct,
 		       TransportAddress *taddr, int count)
 {
 	struct nf_ct_h323_master *info = nfct_help_data(ct);
+	const struct nfct_h323_nat_hooks *nathook;
 	int dir = CTINFO2DIR(ctinfo);
 	int ret = 0;
 	int i;
 	__be16 port;
 	union nf_inet_addr addr;
 	struct nf_conntrack_expect *exp;
-	typeof(nat_q931_hook) nat_q931;
 
 	/* Look for the first related address */
 	for (i = 0; i < count; i++) {
@@ -1279,11 +1228,11 @@ static int expect_q931(struct sk_buff *skb, struct nf_conn *ct,
 	exp->helper = nf_conntrack_helper_q931;
 	exp->flags = NF_CT_EXPECT_PERMANENT;	/* Accept multiple calls */
 
-	nat_q931 = rcu_dereference(nat_q931_hook);
-	if (nat_q931 && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
+	nathook = rcu_dereference(nfct_h323_nat_hook);
+	if (nathook && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
 	    ct->status & IPS_NAT_MASK) {	/* Need NAT */
-		ret = nat_q931(skb, ct, ctinfo, protoff, data,
-			       taddr, i, port, exp);
+		ret = nathook->nat_q931(skb, ct, ctinfo, protoff, data,
+					taddr, i, port, exp);
 	} else {		/* Conntrack only */
 		if (nf_ct_expect_related(exp, 0) == 0) {
 			pr_debug("nf_ct_ras: expect Q.931 ");
@@ -1305,15 +1254,15 @@ static int process_grq(struct sk_buff *skb, struct nf_conn *ct,
 		       unsigned int protoff,
 		       unsigned char **data, GatekeeperRequest *grq)
 {
-	typeof(set_ras_addr_hook) set_ras_addr;
+	const struct nfct_h323_nat_hooks *nathook;
 
 	pr_debug("nf_ct_ras: GRQ\n");
 
-	set_ras_addr = rcu_dereference(set_ras_addr_hook);
-	if (set_ras_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
+	nathook = rcu_dereference(nfct_h323_nat_hook);
+	if (nathook && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
 	    ct->status & IPS_NAT_MASK)	/* NATed */
-		return set_ras_addr(skb, ct, ctinfo, protoff, data,
-				    &grq->rasAddress, 1);
+		return nathook->set_ras_addr(skb, ct, ctinfo, protoff, data,
+					     &grq->rasAddress, 1);
 	return 0;
 }
 
@@ -1367,8 +1316,8 @@ static int process_rrq(struct sk_buff *skb, struct nf_conn *ct,
 		       unsigned char **data, RegistrationRequest *rrq)
 {
 	struct nf_ct_h323_master *info = nfct_help_data(ct);
+	const struct nfct_h323_nat_hooks *nathook;
 	int ret;
-	typeof(set_ras_addr_hook) set_ras_addr;
 
 	pr_debug("nf_ct_ras: RRQ\n");
 
@@ -1378,12 +1327,12 @@ static int process_rrq(struct sk_buff *skb, struct nf_conn *ct,
 	if (ret < 0)
 		return -1;
 
-	set_ras_addr = rcu_dereference(set_ras_addr_hook);
-	if (set_ras_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
+	nathook = rcu_dereference(nfct_h323_nat_hook);
+	if (nathook && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
 	    ct->status & IPS_NAT_MASK) {
-		ret = set_ras_addr(skb, ct, ctinfo, protoff, data,
-				   rrq->rasAddress.item,
-				   rrq->rasAddress.count);
+		ret = nathook->set_ras_addr(skb, ct, ctinfo, protoff, data,
+					    rrq->rasAddress.item,
+					    rrq->rasAddress.count);
 		if (ret < 0)
 			return -1;
 	}
@@ -1403,19 +1352,19 @@ static int process_rcf(struct sk_buff *skb, struct nf_conn *ct,
 		       unsigned char **data, RegistrationConfirm *rcf)
 {
 	struct nf_ct_h323_master *info = nfct_help_data(ct);
+	const struct nfct_h323_nat_hooks *nathook;
 	int dir = CTINFO2DIR(ctinfo);
 	int ret;
 	struct nf_conntrack_expect *exp;
-	typeof(set_sig_addr_hook) set_sig_addr;
 
 	pr_debug("nf_ct_ras: RCF\n");
 
-	set_sig_addr = rcu_dereference(set_sig_addr_hook);
-	if (set_sig_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
+	nathook = rcu_dereference(nfct_h323_nat_hook);
+	if (nathook && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
 	    ct->status & IPS_NAT_MASK) {
-		ret = set_sig_addr(skb, ct, ctinfo, protoff, data,
-					rcf->callSignalAddress.item,
-					rcf->callSignalAddress.count);
+		ret = nathook->set_sig_addr(skb, ct, ctinfo, protoff, data,
+					    rcf->callSignalAddress.item,
+					    rcf->callSignalAddress.count);
 		if (ret < 0)
 			return -1;
 	}
@@ -1454,18 +1403,18 @@ static int process_urq(struct sk_buff *skb, struct nf_conn *ct,
 		       unsigned char **data, UnregistrationRequest *urq)
 {
 	struct nf_ct_h323_master *info = nfct_help_data(ct);
+	const struct nfct_h323_nat_hooks *nathook;
 	int dir = CTINFO2DIR(ctinfo);
 	int ret;
-	typeof(set_sig_addr_hook) set_sig_addr;
 
 	pr_debug("nf_ct_ras: URQ\n");
 
-	set_sig_addr = rcu_dereference(set_sig_addr_hook);
-	if (set_sig_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
+	nathook = rcu_dereference(nfct_h323_nat_hook);
+	if (nathook && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
 	    ct->status & IPS_NAT_MASK) {
-		ret = set_sig_addr(skb, ct, ctinfo, protoff, data,
-				   urq->callSignalAddress.item,
-				   urq->callSignalAddress.count);
+		ret = nathook->set_sig_addr(skb, ct, ctinfo, protoff, data,
+					    urq->callSignalAddress.item,
+					    urq->callSignalAddress.count);
 		if (ret < 0)
 			return -1;
 	}
@@ -1487,39 +1436,42 @@ static int process_arq(struct sk_buff *skb, struct nf_conn *ct,
 		       unsigned char **data, AdmissionRequest *arq)
 {
 	const struct nf_ct_h323_master *info = nfct_help_data(ct);
+	const struct nfct_h323_nat_hooks *nathook;
 	int dir = CTINFO2DIR(ctinfo);
 	__be16 port;
 	union nf_inet_addr addr;
-	typeof(set_h225_addr_hook) set_h225_addr;
 
 	pr_debug("nf_ct_ras: ARQ\n");
 
-	set_h225_addr = rcu_dereference(set_h225_addr_hook);
+	nathook = rcu_dereference(nfct_h323_nat_hook);
+	if (!nathook)
+		return 0;
+
 	if ((arq->options & eAdmissionRequest_destCallSignalAddress) &&
 	    get_h225_addr(ct, *data, &arq->destCallSignalAddress,
 			  &addr, &port) &&
 	    !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
 	    port == info->sig_port[dir] &&
 	    nf_ct_l3num(ct) == NFPROTO_IPV4 &&
-	    set_h225_addr && ct->status & IPS_NAT_MASK) {
+	    ct->status & IPS_NAT_MASK) {
 		/* Answering ARQ */
-		return set_h225_addr(skb, protoff, data, 0,
-				     &arq->destCallSignalAddress,
-				     &ct->tuplehash[!dir].tuple.dst.u3,
-				     info->sig_port[!dir]);
+		return nathook->set_h225_addr(skb, protoff, data, 0,
+					      &arq->destCallSignalAddress,
+					      &ct->tuplehash[!dir].tuple.dst.u3,
+					      info->sig_port[!dir]);
 	}
 
 	if ((arq->options & eAdmissionRequest_srcCallSignalAddress) &&
 	    get_h225_addr(ct, *data, &arq->srcCallSignalAddress,
 			  &addr, &port) &&
 	    !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
-	    set_h225_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
+	    nf_ct_l3num(ct) == NFPROTO_IPV4 &&
 	    ct->status & IPS_NAT_MASK) {
 		/* Calling ARQ */
-		return set_h225_addr(skb, protoff, data, 0,
-				     &arq->srcCallSignalAddress,
-				     &ct->tuplehash[!dir].tuple.dst.u3,
-				     port);
+		return nathook->set_h225_addr(skb, protoff, data, 0,
+					      &arq->srcCallSignalAddress,
+					      &ct->tuplehash[!dir].tuple.dst.u3,
+					      port);
 	}
 
 	return 0;
@@ -1535,7 +1487,6 @@ static int process_acf(struct sk_buff *skb, struct nf_conn *ct,
 	__be16 port;
 	union nf_inet_addr addr;
 	struct nf_conntrack_expect *exp;
-	typeof(set_sig_addr_hook) set_sig_addr;
 
 	pr_debug("nf_ct_ras: ACF\n");
 
@@ -1544,12 +1495,15 @@ static int process_acf(struct sk_buff *skb, struct nf_conn *ct,
 		return 0;
 
 	if (!memcmp(&addr, &ct->tuplehash[dir].tuple.dst.u3, sizeof(addr))) {
+		const struct nfct_h323_nat_hooks *nathook;
+
 		/* Answering ACF */
-		set_sig_addr = rcu_dereference(set_sig_addr_hook);
-		if (set_sig_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
+		nathook = rcu_dereference(nfct_h323_nat_hook);
+		if (nathook && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
 		    ct->status & IPS_NAT_MASK)
-			return set_sig_addr(skb, ct, ctinfo, protoff, data,
-					    &acf->destCallSignalAddress, 1);
+			return nathook->set_sig_addr(skb, ct, ctinfo, protoff,
+						     data,
+						     &acf->destCallSignalAddress, 1);
 		return 0;
 	}
 
@@ -1578,15 +1532,15 @@ static int process_lrq(struct sk_buff *skb, struct nf_conn *ct,
 		       unsigned int protoff,
 		       unsigned char **data, LocationRequest *lrq)
 {
-	typeof(set_ras_addr_hook) set_ras_addr;
+	const struct nfct_h323_nat_hooks *nathook;
 
 	pr_debug("nf_ct_ras: LRQ\n");
 
-	set_ras_addr = rcu_dereference(set_ras_addr_hook);
-	if (set_ras_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
+	nathook = rcu_dereference(nfct_h323_nat_hook);
+	if (nathook && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
 	    ct->status & IPS_NAT_MASK)
-		return set_ras_addr(skb, ct, ctinfo, protoff, data,
-				    &lrq->replyAddress, 1);
+		return nathook->set_ras_addr(skb, ct, ctinfo, protoff, data,
+					     &lrq->replyAddress, 1);
 	return 0;
 }
 
@@ -1634,27 +1588,22 @@ static int process_irr(struct sk_buff *skb, struct nf_conn *ct,
 		       unsigned int protoff,
 		       unsigned char **data, InfoRequestResponse *irr)
 {
+	const struct nfct_h323_nat_hooks *nathook;
 	int ret;
-	typeof(set_ras_addr_hook) set_ras_addr;
-	typeof(set_sig_addr_hook) set_sig_addr;
 
 	pr_debug("nf_ct_ras: IRR\n");
 
-	set_ras_addr = rcu_dereference(set_ras_addr_hook);
-	if (set_ras_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
+	nathook = rcu_dereference(nfct_h323_nat_hook);
+	if (nathook && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
 	    ct->status & IPS_NAT_MASK) {
-		ret = set_ras_addr(skb, ct, ctinfo, protoff, data,
-				   &irr->rasAddress, 1);
+		ret = nathook->set_ras_addr(skb, ct, ctinfo, protoff, data,
+					    &irr->rasAddress, 1);
 		if (ret < 0)
 			return -1;
-	}
 
-	set_sig_addr = rcu_dereference(set_sig_addr_hook);
-	if (set_sig_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
-	    ct->status & IPS_NAT_MASK) {
-		ret = set_sig_addr(skb, ct, ctinfo, protoff, data,
-					irr->callSignalAddress.item,
-					irr->callSignalAddress.count);
+		ret = nathook->set_sig_addr(skb, ct, ctinfo, protoff, data,
+					    irr->callSignalAddress.item,
+					    irr->callSignalAddress.count);
 		if (ret < 0)
 			return -1;
 	}
@@ -1837,17 +1786,6 @@ err1:
 module_init(nf_conntrack_h323_init);
 module_exit(nf_conntrack_h323_fini);
 
-EXPORT_SYMBOL_GPL(get_h225_addr);
-EXPORT_SYMBOL_GPL(set_h245_addr_hook);
-EXPORT_SYMBOL_GPL(set_h225_addr_hook);
-EXPORT_SYMBOL_GPL(set_sig_addr_hook);
-EXPORT_SYMBOL_GPL(set_ras_addr_hook);
-EXPORT_SYMBOL_GPL(nat_rtp_rtcp_hook);
-EXPORT_SYMBOL_GPL(nat_t120_hook);
-EXPORT_SYMBOL_GPL(nat_h245_hook);
-EXPORT_SYMBOL_GPL(nat_callforwarding_hook);
-EXPORT_SYMBOL_GPL(nat_q931_hook);
-
 MODULE_AUTHOR("Jing Min Zhao <zhaojingmin@users.sourceforge.net>");
 MODULE_DESCRIPTION("H.323 connection tracking helper");
 MODULE_LICENSE("GPL");