[NETFILTER]: nf_ct_h323: remove ipv6 module dependency

nf_conntrack_h323 needs ip6_route_output for the call forwarding filter.
Add a ->route function to nf_afinfo and use that to avoid pulling in the
ipv6 module.

Fix the #ifdef for the IPv6 code while I'm at it - the IPv6 support is
only needed when IPv6 conntrack is enabled.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 27 insertions, 7 deletions

diff --git a/include/linux/netfilter.h b/include/linux/netfilter.h
index f42e4362d50d..9bfc7d4f5868 100644
--- a/include/linux/netfilter.h
+++ b/include/linux/netfilter.h
@@ -298,10 +298,12 @@ extern void nf_invalidate_cache(int pf);
    Returns true or false. */
 extern int skb_make_writable(struct sk_buff *skb, unsigned int writable_len);
 
+struct flowi;
 struct nf_afinfo {
         unsigned short  family;
         __sum16         (*checksum)(struct sk_buff *skb, unsigned int hook,
                                     unsigned int dataoff, u_int8_t protocol);
+        int             (*route)(struct dst_entry **dst, struct flowi *fl);
         void            (*saveroute)(const struct sk_buff *skb,
                                      struct nf_info *info);
         int             (*reroute)(struct sk_buff *skb,
diff --git a/net/ipv4/netfilter.c b/net/ipv4/netfilter.c
index d9022467e089..599d448ef57e 100644
--- a/net/ipv4/netfilter.c
+++ b/net/ipv4/netfilter.c
@@ -182,9 +182,15 @@ __sum16 nf_ip_checksum(struct sk_buff *skb, unsigned int hook,
 
 EXPORT_SYMBOL(nf_ip_checksum);
 
+static int nf_ip_route(struct dst_entry **dst, struct flowi *fl)
+{
+        return ip_route_output_key((struct rtable **)dst, fl);
+}
+
 static struct nf_afinfo nf_ip_afinfo = {
         .family         = AF_INET,
         .checksum       = nf_ip_checksum,
+        .route          = nf_ip_route,
         .saveroute      = nf_ip_saveroute,
         .reroute        = nf_ip_reroute,
         .route_key_size = sizeof(struct ip_rt_info),
diff --git a/net/ipv6/netfilter.c b/net/ipv6/netfilter.c
index 175e19f80253..281f732e3c97 100644
--- a/net/ipv6/netfilter.c
+++ b/net/ipv6/netfilter.c
@@ -81,6 +81,12 @@ static int nf_ip6_reroute(struct sk_buff *skb, const struct nf_info *info)
         return 0;
 }
 
+static int nf_ip6_route(struct dst_entry **dst, struct flowi *fl)
+{
+        *dst = ip6_route_output(NULL, fl);
+        return (*dst)->error;
+}
+
 __sum16 nf_ip6_checksum(struct sk_buff *skb, unsigned int hook,
                              unsigned int dataoff, u_int8_t protocol)
 {
@@ -118,6 +124,7 @@ EXPORT_SYMBOL(nf_ip6_checksum);
 static struct nf_afinfo nf_ip6_afinfo = {
         .family         = AF_INET6,
         .checksum       = nf_ip6_checksum,
+        .route          = nf_ip6_route,
         .saveroute      = nf_ip6_saveroute,
         .reroute        = nf_ip6_reroute,
         .route_key_size = sizeof(struct ip6_rt_info),
diff --git a/net/netfilter/nf_conntrack_h323_main.c b/net/netfilter/nf_conntrack_h323_main.c
index f23fd9598e19..c550257b5462 100644
--- a/net/netfilter/nf_conntrack_h323_main.c
+++ b/net/netfilter/nf_conntrack_h323_main.c
@@ -708,9 +708,15 @@ static int callforward_do_filter(union nf_conntrack_address *src,
                                  union nf_conntrack_address *dst,
                                  int family)
 {
+        struct nf_afinfo *afinfo;
         struct flowi fl1, fl2;
         int ret = 0;
 
+        /* rcu_read_lock()ed by nf_hook_slow() */
+        afinfo = nf_get_afinfo(family);
+        if (!afinfo)
+                return 0;
+
         memset(&fl1, 0, sizeof(fl1));
         memset(&fl2, 0, sizeof(fl2));
 
@@ -720,8 +726,8 @@ static int callforward_do_filter(union nf_conntrack_address *src,
 
                 fl1.fl4_dst = src->ip;
                 fl2.fl4_dst = dst->ip;
-                if (ip_route_output_key(&rt1, &fl1) == 0) {
-                        if (ip_route_output_key(&rt2, &fl2) == 0) {
+                if (!afinfo->route((struct dst_entry **)&rt1, &fl1)) {
+                        if (!afinfo->route((struct dst_entry **)&rt2, &fl2)) {
                                 if (rt1->rt_gateway == rt2->rt_gateway &&
                                     rt1->u.dst.dev  == rt2->u.dst.dev)
                                         ret = 1;
@@ -731,16 +737,15 @@ static int callforward_do_filter(union nf_conntrack_address *src,
                 }
                 break;
         }
-#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
+#if defined(CONFIG_NF_CONNTRACK_IPV6) || \
+    defined(CONFIG_NF_CONNTRACK_IPV6_MODULE)
         case AF_INET6: {
                 struct rt6_info *rt1, *rt2;
 
                 memcpy(&fl1.fl6_dst, src, sizeof(fl1.fl6_dst));
                 memcpy(&fl2.fl6_dst, dst, sizeof(fl2.fl6_dst));
-                rt1 = (struct rt6_info *)ip6_route_output(NULL, &fl1);
-                if (rt1) {
-                        rt2 = (struct rt6_info *)ip6_route_output(NULL, &fl2);
-                        if (rt2) {
+                if (!afinfo->route((struct dst_entry **)&rt1, &fl1)) {
+                        if (!afinfo->route((struct dst_entry **)&rt2, &fl2)) {
                                 if (!memcmp(&rt1->rt6i_gateway, &rt2->rt6i_gateway,
                                             sizeof(rt1->rt6i_gateway)) &&
                                     rt1->u.dst.dev == rt2->u.dst.dev)