1 files changed, 100 insertions, 31 deletions

diff --git a/net/netfilter/nf_conntrack_helper.c b/net/netfilter/nf_conntrack_helper.c
index f868b7fbd9b4..96aa637c0932 100644
--- a/net/netfilter/nf_conntrack_helper.c
+++ b/net/netfilter/nf_conntrack_helper.c
@@ -26,23 +26,43 @@
 #include <net/netfilter/nf_conntrack_l4proto.h>
 #include <net/netfilter/nf_conntrack_helper.h>
 #include <net/netfilter/nf_conntrack_core.h>
+#include <net/netfilter/nf_conntrack_extend.h>
 
-static __read_mostly LIST_HEAD(helpers);
+static struct hlist_head *nf_ct_helper_hash __read_mostly;
+static unsigned int nf_ct_helper_hsize __read_mostly;
+static unsigned int nf_ct_helper_count __read_mostly;
+static int nf_ct_helper_vmalloc;
+
+
+/* Stupid hash, but collision free for the default registrations of the
+ * helpers currently in the kernel. */
+static unsigned int helper_hash(const struct nf_conntrack_tuple *tuple)
+{
+	return (((tuple->src.l3num << 8) | tuple->dst.protonum) ^
+		(__force __u16)tuple->src.u.all) % nf_ct_helper_hsize;
+}
 
 struct nf_conntrack_helper *
 __nf_ct_helper_find(const struct nf_conntrack_tuple *tuple)
 {
-	struct nf_conntrack_helper *h;
+	struct nf_conntrack_helper *helper;
+	struct nf_conntrack_tuple_mask mask = { .src.u.all = htons(0xFFFF) };
+	struct hlist_node *n;
+	unsigned int h;
+
+	if (!nf_ct_helper_count)
+		return NULL;
 
-	list_for_each_entry(h, &helpers, list) {
-		if (nf_ct_tuple_mask_cmp(tuple, &h->tuple, &h->mask))
-			return h;
+	h = helper_hash(tuple);
+	hlist_for_each_entry(helper, n, &nf_ct_helper_hash[h], hnode) {
+		if (nf_ct_tuple_src_mask_cmp(tuple, &helper->tuple, &mask))
+			return helper;
 	}
 	return NULL;
 }
 
 struct nf_conntrack_helper *
-nf_ct_helper_find_get( const struct nf_conntrack_tuple *tuple)
+nf_ct_helper_find_get(const struct nf_conntrack_tuple *tuple)
 {
 	struct nf_conntrack_helper *helper;
 
@@ -75,16 +95,32 @@ struct nf_conntrack_helper *
 __nf_conntrack_helper_find_byname(const char *name)
 {
 	struct nf_conntrack_helper *h;
+	struct hlist_node *n;
+	unsigned int i;
 
-	list_for_each_entry(h, &helpers, list) {
-		if (!strcmp(h->name, name))
-			return h;
+	for (i = 0; i < nf_ct_helper_hsize; i++) {
+		hlist_for_each_entry(h, n, &nf_ct_helper_hash[i], hnode) {
+			if (!strcmp(h->name, name))
+				return h;
+		}
 	}
-
 	return NULL;
 }
 EXPORT_SYMBOL_GPL(__nf_conntrack_helper_find_byname);
 
+struct nf_conn_help *nf_ct_helper_ext_add(struct nf_conn *ct, gfp_t gfp)
+{
+	struct nf_conn_help *help;
+
+	help = nf_ct_ext_add(ct, NF_CT_EXT_HELPER, gfp);
+	if (help)
+		INIT_HLIST_HEAD(&help->expectations);
+	else
+		pr_debug("failed to add helper extension area");
+	return help;
+}
+EXPORT_SYMBOL_GPL(nf_ct_helper_ext_add);
+
 static inline int unhelp(struct nf_conntrack_tuple_hash *i,
 			 const struct nf_conntrack_helper *me)
 {
@@ -100,20 +136,13 @@ static inline int unhelp(struct nf_conntrack_tuple_hash *i,
 
 int nf_conntrack_helper_register(struct nf_conntrack_helper *me)
 {
-	int size, ret;
+	unsigned int h = helper_hash(&me->tuple);
 
 	BUG_ON(me->timeout == 0);
 
-	size = ALIGN(sizeof(struct nf_conn), __alignof__(struct nf_conn_help)) +
-	       sizeof(struct nf_conn_help);
-	ret = nf_conntrack_register_cache(NF_CT_F_HELP, "nf_conntrack:help",
-					  size);
-	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);
+	hlist_add_head(&me->hnode, &nf_ct_helper_hash[h]);
+	nf_ct_helper_count++;
 	write_unlock_bh(&nf_conntrack_lock);
 
 	return 0;
@@ -122,29 +151,34 @@ EXPORT_SYMBOL_GPL(nf_conntrack_helper_register);
 
 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;
+	struct nf_conntrack_expect *exp;
+	struct hlist_node *n, *next;
+	unsigned int i;
 
 	/* Need write lock here, to delete helper. */
 	write_lock_bh(&nf_conntrack_lock);
-	list_del(&me->list);
+	hlist_del(&me->hnode);
+	nf_ct_helper_count--;
 
 	/* 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 || exp->helper == me) &&
-		    del_timer(&exp->timeout)) {
-			nf_ct_unlink_expect(exp);
-			nf_conntrack_expect_put(exp);
+	for (i = 0; i < nf_ct_expect_hsize; i++) {
+		hlist_for_each_entry_safe(exp, n, next,
+					  &nf_ct_expect_hash[i], hnode) {
+			struct nf_conn_help *help = nfct_help(exp->master);
+			if ((help->helper == me || exp->helper == me) &&
+			    del_timer(&exp->timeout)) {
+				nf_ct_unlink_expect(exp);
+				nf_ct_expect_put(exp);
+			}
 		}
 	}
 
 	/* Get rid of expecteds, set helpers to NULL. */
-	list_for_each_entry(h, &unconfirmed, list)
+	hlist_for_each_entry(h, n, &unconfirmed, hnode)
 		unhelp(h, me);
 	for (i = 0; i < nf_conntrack_htable_size; i++) {
-		list_for_each_entry(h, &nf_conntrack_hash[i], list)
+		hlist_for_each_entry(h, n, &nf_conntrack_hash[i], hnode)
 			unhelp(h, me);
 	}
 	write_unlock_bh(&nf_conntrack_lock);
@@ -153,3 +187,38 @@ void nf_conntrack_helper_unregister(struct nf_conntrack_helper *me)
 	synchronize_net();
 }
 EXPORT_SYMBOL_GPL(nf_conntrack_helper_unregister);
+
+static struct nf_ct_ext_type helper_extend __read_mostly = {
+	.len	= sizeof(struct nf_conn_help),
+	.align	= __alignof__(struct nf_conn_help),
+	.id	= NF_CT_EXT_HELPER,
+};
+
+int nf_conntrack_helper_init(void)
+{
+	int err;
+
+	nf_ct_helper_hsize = 1; /* gets rounded up to use one page */
+	nf_ct_helper_hash = nf_ct_alloc_hashtable(&nf_ct_helper_hsize,
+						  &nf_ct_helper_vmalloc);
+	if (!nf_ct_helper_hash)
+		return -ENOMEM;
+
+	err = nf_ct_extend_register(&helper_extend);
+	if (err < 0)
+		goto err1;
+
+	return 0;
+
+err1:
+	nf_ct_free_hashtable(nf_ct_helper_hash, nf_ct_helper_vmalloc,
+			     nf_ct_helper_hsize);
+	return err;
+}
+
+void nf_conntrack_helper_fini(void)
+{
+	nf_ct_extend_unregister(&helper_extend);
+	nf_ct_free_hashtable(nf_ct_helper_hash, nf_ct_helper_vmalloc,
+			     nf_ct_helper_hsize);
+}