[NETFILTER]: nf_conntrack: split out helper handling

This patch splits out handling of helpers into its own file
nf_conntrack_helper.c

Signed-off-by: Martin Josefsson <gandalf@wlug.westbo.se>
Signed-off-by: Patrick McHardy <kaber@trash.net>

5 files changed, 165 insertions, 120 deletions

diff --git a/include/net/netfilter/nf_conntrack_core.h b/include/net/netfilter/nf_conntrack_core.h
index 84a8e01941fb..bf8d3008a381 100644
--- a/include/net/netfilter/nf_conntrack_core.h
+++ b/include/net/netfilter/nf_conntrack_core.h
@@ -80,4 +80,6 @@ print_tuple(struct seq_file *s, const struct nf_conntrack_tuple *tuple,
 extern struct list_head *nf_conntrack_hash;
 extern struct list_head nf_conntrack_expect_list;
 extern rwlock_t nf_conntrack_lock ;
+extern struct list_head unconfirmed;
+
 #endif /* _NF_CONNTRACK_CORE_H */
diff --git a/include/net/netfilter/nf_conntrack_helper.h b/include/net/netfilter/nf_conntrack_helper.h
index 3cbd13e22160..fbba9e8b95fc 100644
--- a/include/net/netfilter/nf_conntrack_helper.h
+++ b/include/net/netfilter/nf_conntrack_helper.h
@@ -37,6 +37,16 @@ struct nf_conntrack_helper
         int (*to_nfattr)(struct sk_buff *skb, const struct nf_conn *ct);
 };
 
+extern struct nf_conntrack_helper *
+__nf_ct_helper_find(const struct nf_conntrack_tuple *tuple);
+
+extern struct nf_conntrack_helper *
+nf_ct_helper_find_get( const struct nf_conntrack_tuple *tuple);
+
+extern struct nf_conntrack_helper *
+__nf_conntrack_helper_find_byname(const char *name);
+
+extern void nf_ct_helper_put(struct nf_conntrack_helper *helper);
 extern int nf_conntrack_helper_register(struct nf_conntrack_helper *);
 extern void nf_conntrack_helper_unregister(struct nf_conntrack_helper *);
 
diff --git a/net/netfilter/Makefile b/net/netfilter/Makefile
index d33b9ac01aa7..236376483ef7 100644
--- a/net/netfilter/Makefile
+++ b/net/netfilter/Makefile
@@ -1,5 +1,5 @@
 netfilter-objs := core.o nf_log.o nf_queue.o nf_sockopt.o
-nf_conntrack-objs       := nf_conntrack_core.o nf_conntrack_standalone.o nf_conntrack_expect.o nf_conntrack_l3proto_generic.o nf_conntrack_proto_generic.o nf_conntrack_proto_tcp.o nf_conntrack_proto_udp.o
+nf_conntrack-objs       := nf_conntrack_core.o nf_conntrack_standalone.o nf_conntrack_expect.o nf_conntrack_helper.o nf_conntrack_l3proto_generic.o nf_conntrack_proto_generic.o nf_conntrack_proto_tcp.o nf_conntrack_proto_udp.o
 
 obj-$(CONFIG_NETFILTER) = netfilter.o
 
diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c
index 72fbae4e594c..cf6face67af4 100644
--- a/net/netfilter/nf_conntrack_core.c
+++ b/net/netfilter/nf_conntrack_core.c
@@ -75,13 +75,12 @@ atomic_t nf_conntrack_count = ATOMIC_INIT(0);
 void (*nf_conntrack_destroyed)(struct nf_conn *conntrack) = NULL;
 struct nf_conntrack_protocol **nf_ct_protos[PF_MAX] __read_mostly;
 struct nf_conntrack_l3proto *nf_ct_l3protos[PF_MAX] __read_mostly;
-static LIST_HEAD(helpers);
 unsigned int nf_conntrack_htable_size __read_mostly = 0;
 int nf_conntrack_max __read_mostly;
 struct list_head *nf_conntrack_hash __read_mostly;
 struct nf_conn nf_conntrack_untracked;
 unsigned int nf_ct_log_invalid __read_mostly;
-static LIST_HEAD(unconfirmed);
+LIST_HEAD(unconfirmed);
 static int nf_conntrack_vmalloc __read_mostly;
 
 static unsigned int nf_conntrack_next_id;
@@ -696,46 +695,6 @@ static int early_drop(struct list_head *chain)
         return dropped;
 }
 
-static struct nf_conntrack_helper *
-__nf_ct_helper_find(const struct nf_conntrack_tuple *tuple)
-{
-        struct nf_conntrack_helper *h;
-
-        list_for_each_entry(h, &helpers, list) {
-                if (nf_ct_tuple_mask_cmp(tuple, &h->tuple, &h->mask))
-                        return h;
-        }
-        return NULL;
-}
-
-struct nf_conntrack_helper *
-nf_ct_helper_find_get( const struct nf_conntrack_tuple *tuple)
-{
-        struct nf_conntrack_helper *helper;
-
-        /* need nf_conntrack_lock to assure that helper exists until
-         * try_module_get() is called */
-        read_lock_bh(&nf_conntrack_lock);
-
-        helper = __nf_ct_helper_find(tuple);
-        if (helper) {
-                /* need to increase module usage count to assure helper will
-                 * not go away while the caller is e.g. busy putting a
-                 * conntrack in the hash that uses the helper */
-                if (!try_module_get(helper->me))
-                        helper = NULL;
-        }
-
-        read_unlock_bh(&nf_conntrack_lock);
-
-        return helper;
-}
-
-void nf_ct_helper_put(struct nf_conntrack_helper *helper)
-{
-        module_put(helper->me);
-}
-
 static struct nf_conn *
 __nf_conntrack_alloc(const struct nf_conntrack_tuple *orig,
                      const struct nf_conntrack_tuple *repl,
@@ -1035,83 +994,6 @@ int nf_ct_invert_tuplepr(struct nf_conntrack_tuple *inverse,
                                                      orig->dst.protonum));
 }
 
-int nf_conntrack_helper_register(struct nf_conntrack_helper *me)
-{
-        int ret;
-        BUG_ON(me->timeout == 0);
-
-        ret = nf_conntrack_register_cache(NF_CT_F_HELP, "nf_conntrack:help",
-                                          sizeof(struct nf_conn)
-                                          + sizeof(struct nf_conn_help)
-                                          + __alignof__(struct nf_conn_help));
-        if (ret < 0) {
-                printk(KERN_ERR "nf_conntrack_helper_reigster: Unable to create slab cache for conntracks\n");
-                return ret;
-        }
-        write_lock_bh(&nf_conntrack_lock);
-        list_add(&me->list, &helpers);
-        write_unlock_bh(&nf_conntrack_lock);
-
-        return 0;
-}
-
-struct nf_conntrack_helper *
-__nf_conntrack_helper_find_byname(const char *name)
-{
-        struct nf_conntrack_helper *h;
-
-        list_for_each_entry(h, &helpers, list) {
-                if (!strcmp(h->name, name))
-                        return h;
-        }
-
-        return NULL;
-}
-
-static inline void unhelp(struct nf_conntrack_tuple_hash *i,
-                          const struct nf_conntrack_helper *me)
-{
-        struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(i);
-        struct nf_conn_help *help = nfct_help(ct);
-
-        if (help && help->helper == me) {
-                nf_conntrack_event(IPCT_HELPER, ct);
-                help->helper = NULL;
-        }
-}
-
-void nf_conntrack_helper_unregister(struct nf_conntrack_helper *me)
-{
-        unsigned int i;
-        struct nf_conntrack_tuple_hash *h;
-        struct nf_conntrack_expect *exp, *tmp;
-
-        /* Need write lock here, to delete helper. */
-        write_lock_bh(&nf_conntrack_lock);
-        list_del(&me->list);
-
-        /* Get rid of expectations */
-        list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list, list) {
-                struct nf_conn_help *help = nfct_help(exp->master);
-                if (help->helper == me && del_timer(&exp->timeout)) {
-                        nf_ct_unlink_expect(exp);
-                        nf_conntrack_expect_put(exp);
-                }
-        }
-
-        /* Get rid of expecteds, set helpers to NULL. */
-        list_for_each_entry(h, &unconfirmed, list)
-                unhelp(h, me);
-        for (i = 0; i < nf_conntrack_htable_size; i++) {
-                list_for_each_entry(h, &nf_conntrack_hash[i], list)
-                        unhelp(h, me);
-        }
-        write_unlock_bh(&nf_conntrack_lock);
-
-        /* Someone could be still looking at the helper in a bh. */
-        synchronize_net();
-}
-
 /* Refresh conntrack for this many jiffies and do accounting if do_acct is 1 */
 void __nf_ct_refresh_acct(struct nf_conn *ct,
                           enum ip_conntrack_info ctinfo,
diff --git a/net/netfilter/nf_conntrack_helper.c b/net/netfilter/nf_conntrack_helper.c
new file mode 100644
index 000000000000..ca044875a561
--- /dev/null
+++ b/net/netfilter/nf_conntrack_helper.c
@@ -0,0 +1,151 @@
+/* Helper handling for netfilter. */
+
+/* (C) 1999-2001 Paul `Rusty' Russell
+ * (C) 2002-2006 Netfilter Core Team <coreteam@netfilter.org>
+ * (C) 2003,2004 USAGI/WIDE Project <http://www.linux-ipv6.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.
+ */
+
+#include <linux/types.h>
+#include <linux/netfilter.h>
+#include <linux/module.h>
+#include <linux/skbuff.h>
+#include <linux/vmalloc.h>
+#include <linux/stddef.h>
+#include <linux/slab.h>
+#include <linux/random.h>
+#include <linux/err.h>
+#include <linux/kernel.h>
+#include <linux/netdevice.h>
+
+#define ASSERT_READ_LOCK(x)
+#define ASSERT_WRITE_LOCK(x)
+
+#include <net/netfilter/nf_conntrack.h>
+#include <net/netfilter/nf_conntrack_l3proto.h>
+#include <net/netfilter/nf_conntrack_protocol.h>
+#include <net/netfilter/nf_conntrack_helper.h>
+#include <net/netfilter/nf_conntrack_core.h>
+
+static LIST_HEAD(helpers);
+
+struct nf_conntrack_helper *
+__nf_ct_helper_find(const struct nf_conntrack_tuple *tuple)
+{
+        struct nf_conntrack_helper *h;
+
+        list_for_each_entry(h, &helpers, list) {
+                if (nf_ct_tuple_mask_cmp(tuple, &h->tuple, &h->mask))
+                        return h;
+        }
+        return NULL;
+}
+
+struct nf_conntrack_helper *
+nf_ct_helper_find_get( const struct nf_conntrack_tuple *tuple)
+{
+        struct nf_conntrack_helper *helper;
+
+        /* need nf_conntrack_lock to assure that helper exists until
+         * try_module_get() is called */
+        read_lock_bh(&nf_conntrack_lock);
+
+        helper = __nf_ct_helper_find(tuple);
+        if (helper) {
+                /* need to increase module usage count to assure helper will
+                 * not go away while the caller is e.g. busy putting a
+                 * conntrack in the hash that uses the helper */
+                if (!try_module_get(helper->me))
+                        helper = NULL;
+        }
+
+        read_unlock_bh(&nf_conntrack_lock);
+
+        return helper;
+}
+
+void nf_ct_helper_put(struct nf_conntrack_helper *helper)
+{
+        module_put(helper->me);
+}
+
+struct nf_conntrack_helper *
+__nf_conntrack_helper_find_byname(const char *name)
+{
+        struct nf_conntrack_helper *h;
+
+        list_for_each_entry(h, &helpers, list) {
+                if (!strcmp(h->name, name))
+                        return h;
+        }
+
+        return NULL;
+}
+
+static inline int unhelp(struct nf_conntrack_tuple_hash *i,
+                         const struct nf_conntrack_helper *me)
+{
+        struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(i);
+        struct nf_conn_help *help = nfct_help(ct);
+
+        if (help && help->helper == me) {
+                nf_conntrack_event(IPCT_HELPER, ct);
+                help->helper = NULL;
+        }
+        return 0;
+}
+
+int nf_conntrack_helper_register(struct nf_conntrack_helper *me)
+{
+        int ret;
+        BUG_ON(me->timeout == 0);
+
+        ret = nf_conntrack_register_cache(NF_CT_F_HELP, "nf_conntrack:help",
+                                          sizeof(struct nf_conn)
+                                          + sizeof(struct nf_conn_help)
+                                          + __alignof__(struct nf_conn_help));
+        if (ret < 0) {
+                printk(KERN_ERR "nf_conntrack_helper_register: Unable to create slab cache for conntracks\n");
+                return ret;
+        }
+        write_lock_bh(&nf_conntrack_lock);
+        list_add(&me->list, &helpers);
+        write_unlock_bh(&nf_conntrack_lock);
+
+        return 0;
+}
+
+void nf_conntrack_helper_unregister(struct nf_conntrack_helper *me)
+{
+        unsigned int i;
+        struct nf_conntrack_tuple_hash *h;
+        struct nf_conntrack_expect *exp, *tmp;
+
+        /* Need write lock here, to delete helper. */
+        write_lock_bh(&nf_conntrack_lock);
+        list_del(&me->list);
+
+        /* Get rid of expectations */
+        list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list, list) {
+                struct nf_conn_help *help = nfct_help(exp->master);
+                if (help->helper == me && del_timer(&exp->timeout)) {
+                        nf_ct_unlink_expect(exp);
+                        nf_conntrack_expect_put(exp);
+                }
+        }
+
+        /* Get rid of expecteds, set helpers to NULL. */
+        list_for_each_entry(h, &unconfirmed, list)
+                unhelp(h, me);
+        for (i = 0; i < nf_conntrack_htable_size; i++) {
+                list_for_each_entry(h, &nf_conntrack_hash[i], list)
+                        unhelp(h, me);
+        }
+        write_unlock_bh(&nf_conntrack_lock);
+
+        /* Someone could be still looking at the helper in a bh. */
+        synchronize_net();
+}