[NETFILTER]: nf_conntrack: split out expectation handling
authorMartin Josefsson <gandalf@wlug.westbo.se>
Wed, 29 Nov 2006 01:34:58 +0000 (02:34 +0100)
committerDavid S. Miller <davem@sunset.davemloft.net>
Sun, 3 Dec 2006 05:31:04 +0000 (21:31 -0800)
This patch splits out expectation handling into its own file
nf_conntrack_expect.c

Signed-off-by: Martin Josefsson <gandalf@wlug.westbo.se>
Signed-off-by: Patrick McHardy <kaber@trash.net>
include/net/netfilter/nf_conntrack.h
include/net/netfilter/nf_conntrack_core.h
include/net/netfilter/nf_conntrack_expect.h [new file with mode: 0644]
include/net/netfilter/nf_conntrack_helper.h
net/netfilter/Makefile
net/netfilter/nf_conntrack_core.c
net/netfilter/nf_conntrack_expect.c [new file with mode: 0644]
net/netfilter/nf_conntrack_ftp.c
net/netfilter/nf_conntrack_netlink.c
net/netfilter/nf_conntrack_standalone.c

index 1fbd8193d5f13f82b0b035cca412c0ef9ae479ba..9d2581fc04be24b9189b71c1158092867829111c 100644 (file)
@@ -124,44 +124,6 @@ struct nf_conn
        char data[0];
 };
 
-struct nf_conntrack_expect
-{
-       /* Internal linked list (global expectation list) */
-       struct list_head list;
-
-       /* We expect this tuple, with the following mask */
-       struct nf_conntrack_tuple tuple, mask;
-       /* Function to call after setup and insertion */
-       void (*expectfn)(struct nf_conn *new,
-                        struct nf_conntrack_expect *this);
-
-       /* The conntrack of the master connection */
-       struct nf_conn *master;
-
-       /* Timer function; deletes the expectation. */
-       struct timer_list timeout;
-
-       /* Usage count. */
-       atomic_t use;
-
-       /* Unique ID */
-       unsigned int id;
-
-       /* Flags */
-       unsigned int flags;
-
-#ifdef CONFIG_NF_NAT_NEEDED
-       /* This is the original per-proto part, used to map the
-        * expected connection the way the recipient expects. */
-       union nf_conntrack_manip_proto saved_proto;
-       /* Direction relative to the master connection. */
-       enum ip_conntrack_dir dir;
-#endif
-};
-
-#define NF_CT_EXPECT_PERMANENT 0x1
-
 static inline struct nf_conn *
 nf_ct_tuplehash_to_ctrack(const struct nf_conntrack_tuple_hash *hash)
 {
@@ -208,16 +170,6 @@ __nf_conntrack_find(const struct nf_conntrack_tuple *tuple,
 
 extern void nf_conntrack_hash_insert(struct nf_conn *ct);
 
-extern struct nf_conntrack_expect *
-__nf_conntrack_expect_find(const struct nf_conntrack_tuple *tuple);
-
-extern struct nf_conntrack_expect *
-nf_conntrack_expect_find(const struct nf_conntrack_tuple *tuple);
-
-extern void nf_ct_unlink_expect(struct nf_conntrack_expect *exp);
-
-extern void nf_ct_remove_expectations(struct nf_conn *ct);
-
 extern void nf_conntrack_flush(void);
 
 extern struct nf_conntrack_helper *
@@ -295,6 +247,7 @@ extern int nf_conntrack_checksum;
 #ifdef CONFIG_NF_CONNTRACK_EVENTS
 #include <linux/notifier.h>
 #include <linux/interrupt.h>
+#include <net/netfilter/nf_conntrack_expect.h>
 
 struct nf_conntrack_ecache {
        struct nf_conn *ct;
index da254525a4ceb739f63abc7d784573c3cc8b2320..84a8e01941fbbdb342a336203e488fc3117d7b2f 100644 (file)
@@ -13,6 +13,8 @@
 #define _NF_CONNTRACK_CORE_H
 
 #include <linux/netfilter.h>
+#include <net/netfilter/nf_conntrack_l3proto.h>
+#include <net/netfilter/nf_conntrack_protocol.h>
 
 /* This header is used to share core functionality between the
    standalone connection tracking module, and the compatibility layer's use
@@ -70,6 +72,11 @@ static inline int nf_conntrack_confirm(struct sk_buff **pskb)
 
 extern void __nf_conntrack_attach(struct sk_buff *nskb, struct sk_buff *skb);
 
+int
+print_tuple(struct seq_file *s, const struct nf_conntrack_tuple *tuple,
+           struct nf_conntrack_l3proto *l3proto,
+           struct nf_conntrack_protocol *proto);
+
 extern struct list_head *nf_conntrack_hash;
 extern struct list_head nf_conntrack_expect_list;
 extern rwlock_t nf_conntrack_lock ;
diff --git a/include/net/netfilter/nf_conntrack_expect.h b/include/net/netfilter/nf_conntrack_expect.h
new file mode 100644 (file)
index 0000000..5aa483e
--- /dev/null
@@ -0,0 +1,72 @@
+/*
+ * connection tracking expectations.
+ */
+
+#ifndef _NF_CONNTRACK_EXPECT_H
+#define _NF_CONNTRACK_EXPECT_H
+#include <net/netfilter/nf_conntrack.h>
+
+extern struct list_head nf_conntrack_expect_list;
+extern kmem_cache_t *nf_conntrack_expect_cachep;
+extern struct file_operations exp_file_ops;
+
+struct nf_conntrack_expect
+{
+       /* Internal linked list (global expectation list) */
+       struct list_head list;
+
+       /* We expect this tuple, with the following mask */
+       struct nf_conntrack_tuple tuple, mask;
+
+       /* Function to call after setup and insertion */
+       void (*expectfn)(struct nf_conn *new,
+                        struct nf_conntrack_expect *this);
+
+       /* The conntrack of the master connection */
+       struct nf_conn *master;
+
+       /* Timer function; deletes the expectation. */
+       struct timer_list timeout;
+
+       /* Usage count. */
+       atomic_t use;
+
+       /* Unique ID */
+       unsigned int id;
+
+       /* Flags */
+       unsigned int flags;
+
+#ifdef CONFIG_NF_NAT_NEEDED
+       /* This is the original per-proto part, used to map the
+        * expected connection the way the recipient expects. */
+       union nf_conntrack_manip_proto saved_proto;
+       /* Direction relative to the master connection. */
+       enum ip_conntrack_dir dir;
+#endif
+};
+
+#define NF_CT_EXPECT_PERMANENT 0x1
+
+
+struct nf_conntrack_expect *
+__nf_conntrack_expect_find(const struct nf_conntrack_tuple *tuple);
+
+struct nf_conntrack_expect *
+nf_conntrack_expect_find(const struct nf_conntrack_tuple *tuple);
+
+struct nf_conntrack_expect *
+find_expectation(const struct nf_conntrack_tuple *tuple);
+
+void nf_ct_unlink_expect(struct nf_conntrack_expect *exp);
+void nf_ct_remove_expectations(struct nf_conn *ct);
+void nf_conntrack_unexpect_related(struct nf_conntrack_expect *exp);
+
+/* Allocate space for an expectation: this is mandatory before calling
+   nf_conntrack_expect_related.  You will have to call put afterwards. */
+struct nf_conntrack_expect *nf_conntrack_expect_alloc(struct nf_conn *me);
+void nf_conntrack_expect_put(struct nf_conntrack_expect *exp);
+int nf_conntrack_expect_related(struct nf_conntrack_expect *expect);
+
+#endif /*_NF_CONNTRACK_EXPECT_H*/
+
index 86ec8174ad027cbfc68a3510cc34dfa737c9c4a7..3cbd13e2216052d1644da682586ee6a704a86058 100644 (file)
@@ -40,14 +40,4 @@ struct nf_conntrack_helper
 extern int nf_conntrack_helper_register(struct nf_conntrack_helper *);
 extern void nf_conntrack_helper_unregister(struct nf_conntrack_helper *);
 
-/* Allocate space for an expectation: this is mandatory before calling
-   nf_conntrack_expect_related.  You will have to call put afterwards. */
-extern struct nf_conntrack_expect *
-nf_conntrack_expect_alloc(struct nf_conn *master);
-extern void nf_conntrack_expect_put(struct nf_conntrack_expect *exp);
-
-/* Add an expected connection: can have more than one per connection */
-extern int nf_conntrack_expect_related(struct nf_conntrack_expect *exp);
-extern void nf_conntrack_unexpect_related(struct nf_conntrack_expect *exp);
-
 #endif /*_NF_CONNTRACK_HELPER_H*/
index a74be492fd0a4ca195dd864f00ec8ab74391b701..d33b9ac01aa76694c8da09ed84fdfcab3b813753 100644 (file)
@@ -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_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_l3proto_generic.o nf_conntrack_proto_generic.o nf_conntrack_proto_tcp.o nf_conntrack_proto_udp.o
 
 obj-$(CONFIG_NETFILTER) = netfilter.o
 
index de0567b1f4223a898f9004a2c436c9cf7110ac9d..72fbae4e594cbb47995614f84f0fc39c1a92b3a9 100644 (file)
@@ -55,6 +55,7 @@
 #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_expect.h>
 #include <net/netfilter/nf_conntrack_helper.h>
 #include <net/netfilter/nf_conntrack_core.h>
 
@@ -72,21 +73,19 @@ DEFINE_RWLOCK(nf_conntrack_lock);
 atomic_t nf_conntrack_count = ATOMIC_INIT(0);
 
 void (*nf_conntrack_destroyed)(struct nf_conn *conntrack) = NULL;
-LIST_HEAD(nf_conntrack_expect_list);
 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;
-static kmem_cache_t *nf_conntrack_expect_cachep __read_mostly;
 struct nf_conn nf_conntrack_untracked;
 unsigned int nf_ct_log_invalid __read_mostly;
 static LIST_HEAD(unconfirmed);
 static int nf_conntrack_vmalloc __read_mostly;
 
 static unsigned int nf_conntrack_next_id;
-static unsigned int nf_conntrack_expect_next_id;
+
 #ifdef CONFIG_NF_CONNTRACK_EVENTS
 ATOMIC_NOTIFIER_HEAD(nf_conntrack_chain);
 ATOMIC_NOTIFIER_HEAD(nf_conntrack_expect_chain);
@@ -438,103 +437,6 @@ nf_ct_invert_tuple(struct nf_conntrack_tuple *inverse,
        return protocol->invert_tuple(inverse, orig);
 }
 
-/* nf_conntrack_expect helper functions */
-void nf_ct_unlink_expect(struct nf_conntrack_expect *exp)
-{
-       struct nf_conn_help *master_help = nfct_help(exp->master);
-
-       NF_CT_ASSERT(master_help);
-       ASSERT_WRITE_LOCK(&nf_conntrack_lock);
-       NF_CT_ASSERT(!timer_pending(&exp->timeout));
-
-       list_del(&exp->list);
-       NF_CT_STAT_INC(expect_delete);
-       master_help->expecting--;
-       nf_conntrack_expect_put(exp);
-}
-
-static void expectation_timed_out(unsigned long ul_expect)
-{
-       struct nf_conntrack_expect *exp = (void *)ul_expect;
-
-       write_lock_bh(&nf_conntrack_lock);
-       nf_ct_unlink_expect(exp);
-       write_unlock_bh(&nf_conntrack_lock);
-       nf_conntrack_expect_put(exp);
-}
-
-struct nf_conntrack_expect *
-__nf_conntrack_expect_find(const struct nf_conntrack_tuple *tuple)
-{
-       struct nf_conntrack_expect *i;
-       
-       list_for_each_entry(i, &nf_conntrack_expect_list, list) {
-               if (nf_ct_tuple_mask_cmp(tuple, &i->tuple, &i->mask))
-                       return i;
-       }
-       return NULL;
-}
-
-/* Just find a expectation corresponding to a tuple. */
-struct nf_conntrack_expect *
-nf_conntrack_expect_find(const struct nf_conntrack_tuple *tuple)
-{
-       struct nf_conntrack_expect *i;
-       
-       read_lock_bh(&nf_conntrack_lock);
-       i = __nf_conntrack_expect_find(tuple);
-       if (i)
-               atomic_inc(&i->use);
-       read_unlock_bh(&nf_conntrack_lock);
-
-       return i;
-}
-
-/* If an expectation for this connection is found, it gets delete from
- * global list then returned. */
-static struct nf_conntrack_expect *
-find_expectation(const struct nf_conntrack_tuple *tuple)
-{
-       struct nf_conntrack_expect *i;
-
-       list_for_each_entry(i, &nf_conntrack_expect_list, list) {
-       /* If master is not in hash table yet (ie. packet hasn't left
-          this machine yet), how can other end know about expected?
-          Hence these are not the droids you are looking for (if
-          master ct never got confirmed, we'd hold a reference to it
-          and weird things would happen to future packets). */
-               if (nf_ct_tuple_mask_cmp(tuple, &i->tuple, &i->mask)
-                   && nf_ct_is_confirmed(i->master)) {
-                       if (i->flags & NF_CT_EXPECT_PERMANENT) {
-                               atomic_inc(&i->use);
-                               return i;
-                       } else if (del_timer(&i->timeout)) {
-                               nf_ct_unlink_expect(i);
-                               return i;
-                       }
-               }
-       }
-       return NULL;
-}
-
-/* delete all expectations for this conntrack */
-void nf_ct_remove_expectations(struct nf_conn *ct)
-{
-       struct nf_conntrack_expect *i, *tmp;
-       struct nf_conn_help *help = nfct_help(ct);
-
-       /* Optimization: most connection never expect any others. */
-       if (!help || help->expecting == 0)
-               return;
-
-       list_for_each_entry_safe(i, tmp, &nf_conntrack_expect_list, list) {
-               if (i->master == ct && del_timer(&i->timeout)) {
-                       nf_ct_unlink_expect(i);
-                       nf_conntrack_expect_put(i);
-               }
-       }
-}
-
 static void
 clean_from_lists(struct nf_conn *ct)
 {
@@ -1133,169 +1035,6 @@ int nf_ct_invert_tuplepr(struct nf_conntrack_tuple *inverse,
                                                     orig->dst.protonum));
 }
 
-/* Would two expected things clash? */
-static inline int expect_clash(const struct nf_conntrack_expect *a,
-                              const struct nf_conntrack_expect *b)
-{
-       /* Part covered by intersection of masks must be unequal,
-          otherwise they clash */
-       struct nf_conntrack_tuple intersect_mask;
-       int count;
-
-       intersect_mask.src.l3num = a->mask.src.l3num & b->mask.src.l3num;
-       intersect_mask.src.u.all = a->mask.src.u.all & b->mask.src.u.all;
-       intersect_mask.dst.u.all = a->mask.dst.u.all & b->mask.dst.u.all;
-       intersect_mask.dst.protonum = a->mask.dst.protonum
-                                       & b->mask.dst.protonum;
-
-       for (count = 0; count < NF_CT_TUPLE_L3SIZE; count++){
-               intersect_mask.src.u3.all[count] =
-                       a->mask.src.u3.all[count] & b->mask.src.u3.all[count];
-       }
-
-       for (count = 0; count < NF_CT_TUPLE_L3SIZE; count++){
-               intersect_mask.dst.u3.all[count] =
-                       a->mask.dst.u3.all[count] & b->mask.dst.u3.all[count];
-       }
-
-       return nf_ct_tuple_mask_cmp(&a->tuple, &b->tuple, &intersect_mask);
-}
-
-static inline int expect_matches(const struct nf_conntrack_expect *a,
-                                const struct nf_conntrack_expect *b)
-{
-       return a->master == b->master
-               && nf_ct_tuple_equal(&a->tuple, &b->tuple)
-               && nf_ct_tuple_equal(&a->mask, &b->mask);
-}
-
-/* Generally a bad idea to call this: could have matched already. */
-void nf_conntrack_unexpect_related(struct nf_conntrack_expect *exp)
-{
-       struct nf_conntrack_expect *i;
-
-       write_lock_bh(&nf_conntrack_lock);
-       /* choose the the oldest expectation to evict */
-       list_for_each_entry_reverse(i, &nf_conntrack_expect_list, list) {
-               if (expect_matches(i, exp) && del_timer(&i->timeout)) {
-                       nf_ct_unlink_expect(i);
-                       write_unlock_bh(&nf_conntrack_lock);
-                       nf_conntrack_expect_put(i);
-                       return;
-               }
-       }
-       write_unlock_bh(&nf_conntrack_lock);
-}
-
-/* We don't increase the master conntrack refcount for non-fulfilled
- * conntracks. During the conntrack destruction, the expectations are
- * always killed before the conntrack itself */
-struct nf_conntrack_expect *nf_conntrack_expect_alloc(struct nf_conn *me)
-{
-       struct nf_conntrack_expect *new;
-
-       new = kmem_cache_alloc(nf_conntrack_expect_cachep, GFP_ATOMIC);
-       if (!new) {
-               DEBUGP("expect_related: OOM allocating expect\n");
-               return NULL;
-       }
-       new->master = me;
-       atomic_set(&new->use, 1);
-       return new;
-}
-
-void nf_conntrack_expect_put(struct nf_conntrack_expect *exp)
-{
-       if (atomic_dec_and_test(&exp->use))
-               kmem_cache_free(nf_conntrack_expect_cachep, exp);
-}
-
-static void nf_conntrack_expect_insert(struct nf_conntrack_expect *exp)
-{
-       struct nf_conn_help *master_help = nfct_help(exp->master);
-
-       atomic_inc(&exp->use);
-       master_help->expecting++;
-       list_add(&exp->list, &nf_conntrack_expect_list);
-
-       init_timer(&exp->timeout);
-       exp->timeout.data = (unsigned long)exp;
-       exp->timeout.function = expectation_timed_out;
-       exp->timeout.expires = jiffies + master_help->helper->timeout * HZ;
-       add_timer(&exp->timeout);
-
-       exp->id = ++nf_conntrack_expect_next_id;
-       atomic_inc(&exp->use);
-       NF_CT_STAT_INC(expect_create);
-}
-
-/* Race with expectations being used means we could have none to find; OK. */
-static void evict_oldest_expect(struct nf_conn *master)
-{
-       struct nf_conntrack_expect *i;
-
-       list_for_each_entry_reverse(i, &nf_conntrack_expect_list, list) {
-               if (i->master == master) {
-                       if (del_timer(&i->timeout)) {
-                               nf_ct_unlink_expect(i);
-                               nf_conntrack_expect_put(i);
-                       }
-                       break;
-               }
-       }
-}
-
-static inline int refresh_timer(struct nf_conntrack_expect *i)
-{
-       struct nf_conn_help *master_help = nfct_help(i->master);
-
-       if (!del_timer(&i->timeout))
-               return 0;
-
-       i->timeout.expires = jiffies + master_help->helper->timeout*HZ;
-       add_timer(&i->timeout);
-       return 1;
-}
-
-int nf_conntrack_expect_related(struct nf_conntrack_expect *expect)
-{
-       struct nf_conntrack_expect *i;
-       struct nf_conn *master = expect->master;
-       struct nf_conn_help *master_help = nfct_help(master);
-       int ret;
-
-       NF_CT_ASSERT(master_help);
-
-       DEBUGP("nf_conntrack_expect_related %p\n", related_to);
-       DEBUGP("tuple: "); NF_CT_DUMP_TUPLE(&expect->tuple);
-       DEBUGP("mask:  "); NF_CT_DUMP_TUPLE(&expect->mask);
-
-       write_lock_bh(&nf_conntrack_lock);
-       list_for_each_entry(i, &nf_conntrack_expect_list, list) {
-               if (expect_matches(i, expect)) {
-                       /* Refresh timer: if it's dying, ignore.. */
-                       if (refresh_timer(i)) {
-                               ret = 0;
-                               goto out;
-                       }
-               } else if (expect_clash(i, expect)) {
-                       ret = -EBUSY;
-                       goto out;
-               }
-       }
-       /* Will be over limit? */
-       if (master_help->helper->max_expected &&
-           master_help->expecting >= master_help->helper->max_expected)
-               evict_oldest_expect(master);
-
-       nf_conntrack_expect_insert(expect);
-       nf_conntrack_expect_event(IPEXP_NEW, expect);
-       ret = 0;
-out:
-       write_unlock_bh(&nf_conntrack_lock);
-       return ret;
-}
-
 int nf_conntrack_helper_register(struct nf_conntrack_helper *me)
 {
        int ret;
diff --git a/net/netfilter/nf_conntrack_expect.c b/net/netfilter/nf_conntrack_expect.c
new file mode 100644 (file)
index 0000000..076e678
--- /dev/null
@@ -0,0 +1,365 @@
+/* Expectation handling for nf_conntrack. */
+
+/* (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/skbuff.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/stddef.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/percpu.h>
+#include <linux/kernel.h>
+
+#include <net/netfilter/nf_conntrack.h>
+#include <net/netfilter/nf_conntrack_core.h>
+#include <net/netfilter/nf_conntrack_expect.h>
+#include <net/netfilter/nf_conntrack_helper.h>
+#include <net/netfilter/nf_conntrack_tuple.h>
+
+LIST_HEAD(nf_conntrack_expect_list);
+kmem_cache_t *nf_conntrack_expect_cachep __read_mostly;
+DECLARE_PER_CPU(struct ip_conntrack_stat, nf_conntrack_stat);
+static unsigned int nf_conntrack_expect_next_id;
+
+/* nf_conntrack_expect helper functions */
+void nf_ct_unlink_expect(struct nf_conntrack_expect *exp)
+{
+       struct nf_conn_help *master_help = nfct_help(exp->master);
+
+       NF_CT_ASSERT(master_help);
+       NF_CT_ASSERT(!timer_pending(&exp->timeout));
+
+       list_del(&exp->list);
+       NF_CT_STAT_INC(expect_delete);
+       master_help->expecting--;
+       nf_conntrack_expect_put(exp);
+}
+
+static void expectation_timed_out(unsigned long ul_expect)
+{
+       struct nf_conntrack_expect *exp = (void *)ul_expect;
+
+       write_lock_bh(&nf_conntrack_lock);
+       nf_ct_unlink_expect(exp);
+       write_unlock_bh(&nf_conntrack_lock);
+       nf_conntrack_expect_put(exp);
+}
+
+struct nf_conntrack_expect *
+__nf_conntrack_expect_find(const struct nf_conntrack_tuple *tuple)
+{
+       struct nf_conntrack_expect *i;
+
+       list_for_each_entry(i, &nf_conntrack_expect_list, list) {
+               if (nf_ct_tuple_mask_cmp(tuple, &i->tuple, &i->mask))
+                       return i;
+       }
+       return NULL;
+}
+
+/* Just find a expectation corresponding to a tuple. */
+struct nf_conntrack_expect *
+nf_conntrack_expect_find(const struct nf_conntrack_tuple *tuple)
+{
+       struct nf_conntrack_expect *i;
+
+       read_lock_bh(&nf_conntrack_lock);
+       i = __nf_conntrack_expect_find(tuple);
+       if (i)
+               atomic_inc(&i->use);
+       read_unlock_bh(&nf_conntrack_lock);
+
+       return i;
+}
+
+/* If an expectation for this connection is found, it gets delete from
+ * global list then returned. */
+struct nf_conntrack_expect *
+find_expectation(const struct nf_conntrack_tuple *tuple)
+{
+       struct nf_conntrack_expect *i;
+
+       list_for_each_entry(i, &nf_conntrack_expect_list, list) {
+       /* If master is not in hash table yet (ie. packet hasn't left
+          this machine yet), how can other end know about expected?
+          Hence these are not the droids you are looking for (if
+          master ct never got confirmed, we'd hold a reference to it
+          and weird things would happen to future packets). */
+               if (nf_ct_tuple_mask_cmp(tuple, &i->tuple, &i->mask)
+                   && nf_ct_is_confirmed(i->master)) {
+                       if (i->flags & NF_CT_EXPECT_PERMANENT) {
+                               atomic_inc(&i->use);
+                               return i;
+                       } else if (del_timer(&i->timeout)) {
+                               nf_ct_unlink_expect(i);
+                               return i;
+                       }
+               }
+       }
+       return NULL;
+}
+
+/* delete all expectations for this conntrack */
+void nf_ct_remove_expectations(struct nf_conn *ct)
+{
+       struct nf_conntrack_expect *i, *tmp;
+       struct nf_conn_help *help = nfct_help(ct);
+
+       /* Optimization: most connection never expect any others. */
+       if (!help || help->expecting == 0)
+               return;
+
+       list_for_each_entry_safe(i, tmp, &nf_conntrack_expect_list, list) {
+               if (i->master == ct && del_timer(&i->timeout)) {
+                       nf_ct_unlink_expect(i);
+                       nf_conntrack_expect_put(i);
+               }
+       }
+}
+
+/* Would two expected things clash? */
+static inline int expect_clash(const struct nf_conntrack_expect *a,
+                              const struct nf_conntrack_expect *b)
+{
+       /* Part covered by intersection of masks must be unequal,
+          otherwise they clash */
+       struct nf_conntrack_tuple intersect_mask;
+       int count;
+
+       intersect_mask.src.l3num = a->mask.src.l3num & b->mask.src.l3num;
+       intersect_mask.src.u.all = a->mask.src.u.all & b->mask.src.u.all;
+       intersect_mask.dst.u.all = a->mask.dst.u.all & b->mask.dst.u.all;
+       intersect_mask.dst.protonum = a->mask.dst.protonum
+                                       & b->mask.dst.protonum;
+
+       for (count = 0; count < NF_CT_TUPLE_L3SIZE; count++){
+               intersect_mask.src.u3.all[count] =
+                       a->mask.src.u3.all[count] & b->mask.src.u3.all[count];
+       }
+
+       for (count = 0; count < NF_CT_TUPLE_L3SIZE; count++){
+               intersect_mask.dst.u3.all[count] =
+                       a->mask.dst.u3.all[count] & b->mask.dst.u3.all[count];
+       }
+
+       return nf_ct_tuple_mask_cmp(&a->tuple, &b->tuple, &intersect_mask);
+}
+
+static inline int expect_matches(const struct nf_conntrack_expect *a,
+                                const struct nf_conntrack_expect *b)
+{
+       return a->master == b->master
+               && nf_ct_tuple_equal(&a->tuple, &b->tuple)
+               && nf_ct_tuple_equal(&a->mask, &b->mask);
+}
+
+/* Generally a bad idea to call this: could have matched already. */
+void nf_conntrack_unexpect_related(struct nf_conntrack_expect *exp)
+{
+       struct nf_conntrack_expect *i;
+
+       write_lock_bh(&nf_conntrack_lock);
+       /* choose the the oldest expectation to evict */
+       list_for_each_entry_reverse(i, &nf_conntrack_expect_list, list) {
+               if (expect_matches(i, exp) && del_timer(&i->timeout)) {
+                       nf_ct_unlink_expect(i);
+                       write_unlock_bh(&nf_conntrack_lock);
+                       nf_conntrack_expect_put(i);
+                       return;
+               }
+       }
+       write_unlock_bh(&nf_conntrack_lock);
+}
+
+/* We don't increase the master conntrack refcount for non-fulfilled
+ * conntracks. During the conntrack destruction, the expectations are
+ * always killed before the conntrack itself */
+struct nf_conntrack_expect *nf_conntrack_expect_alloc(struct nf_conn *me)
+{
+       struct nf_conntrack_expect *new;
+
+       new = kmem_cache_alloc(nf_conntrack_expect_cachep, GFP_ATOMIC);
+       if (!new)
+               return NULL;
+
+       new->master = me;
+       atomic_set(&new->use, 1);
+       return new;
+}
+
+void nf_conntrack_expect_put(struct nf_conntrack_expect *exp)
+{
+       if (atomic_dec_and_test(&exp->use))
+               kmem_cache_free(nf_conntrack_expect_cachep, exp);
+}
+
+static void nf_conntrack_expect_insert(struct nf_conntrack_expect *exp)
+{
+       struct nf_conn_help *master_help = nfct_help(exp->master);
+
+       atomic_inc(&exp->use);
+       master_help->expecting++;
+       list_add(&exp->list, &nf_conntrack_expect_list);
+
+       init_timer(&exp->timeout);
+       exp->timeout.data = (unsigned long)exp;
+       exp->timeout.function = expectation_timed_out;
+       exp->timeout.expires = jiffies + master_help->helper->timeout * HZ;
+       add_timer(&exp->timeout);
+
+       exp->id = ++nf_conntrack_expect_next_id;
+       atomic_inc(&exp->use);
+       NF_CT_STAT_INC(expect_create);
+}
+
+/* Race with expectations being used means we could have none to find; OK. */
+static void evict_oldest_expect(struct nf_conn *master)
+{
+       struct nf_conntrack_expect *i;
+
+       list_for_each_entry_reverse(i, &nf_conntrack_expect_list, list) {
+               if (i->master == master) {
+                       if (del_timer(&i->timeout)) {
+                               nf_ct_unlink_expect(i);
+                               nf_conntrack_expect_put(i);
+                       }
+                       break;
+               }
+       }
+}
+
+static inline int refresh_timer(struct nf_conntrack_expect *i)
+{
+       struct nf_conn_help *master_help = nfct_help(i->master);
+
+       if (!del_timer(&i->timeout))
+               return 0;
+
+       i->timeout.expires = jiffies + master_help->helper->timeout*HZ;
+       add_timer(&i->timeout);
+       return 1;
+}
+
+int nf_conntrack_expect_related(struct nf_conntrack_expect *expect)
+{
+       struct nf_conntrack_expect *i;
+       struct nf_conn *master = expect->master;
+       struct nf_conn_help *master_help = nfct_help(master);
+       int ret;
+
+       NF_CT_ASSERT(master_help);
+
+       write_lock_bh(&nf_conntrack_lock);
+       list_for_each_entry(i, &nf_conntrack_expect_list, list) {
+               if (expect_matches(i, expect)) {
+                       /* Refresh timer: if it's dying, ignore.. */
+                       if (refresh_timer(i)) {
+                               ret = 0;
+                               goto out;
+                       }
+               } else if (expect_clash(i, expect)) {
+                       ret = -EBUSY;
+                       goto out;
+               }
+       }
+       /* Will be over limit? */
+       if (master_help->helper->max_expected &&
+           master_help->expecting >= master_help->helper->max_expected)
+               evict_oldest_expect(master);
+
+       nf_conntrack_expect_insert(expect);
+       nf_conntrack_expect_event(IPEXP_NEW, expect);
+       ret = 0;
+out:
+       write_unlock_bh(&nf_conntrack_lock);
+       return ret;
+}
+
+#ifdef CONFIG_PROC_FS
+static void *exp_seq_start(struct seq_file *s, loff_t *pos)
+{
+       struct list_head *e = &nf_conntrack_expect_list;
+       loff_t i;
+
+       /* strange seq_file api calls stop even if we fail,
+        * thus we need to grab lock since stop unlocks */
+       read_lock_bh(&nf_conntrack_lock);
+
+       if (list_empty(e))
+               return NULL;
+
+       for (i = 0; i <= *pos; i++) {
+               e = e->next;
+               if (e == &nf_conntrack_expect_list)
+                       return NULL;
+       }
+       return e;
+}
+
+static void *exp_seq_next(struct seq_file *s, void *v, loff_t *pos)
+{
+       struct list_head *e = v;
+
+       ++*pos;
+       e = e->next;
+
+       if (e == &nf_conntrack_expect_list)
+               return NULL;
+
+       return e;
+}
+
+static void exp_seq_stop(struct seq_file *s, void *v)
+{
+       read_unlock_bh(&nf_conntrack_lock);
+}
+
+static int exp_seq_show(struct seq_file *s, void *v)
+{
+       struct nf_conntrack_expect *expect = v;
+
+       if (expect->timeout.function)
+               seq_printf(s, "%ld ", timer_pending(&expect->timeout)
+                          ? (long)(expect->timeout.expires - jiffies)/HZ : 0);
+       else
+               seq_printf(s, "- ");
+       seq_printf(s, "l3proto = %u proto=%u ",
+                  expect->tuple.src.l3num,
+                  expect->tuple.dst.protonum);
+       print_tuple(s, &expect->tuple,
+                   __nf_ct_l3proto_find(expect->tuple.src.l3num),
+                   __nf_ct_proto_find(expect->tuple.src.l3num,
+                                      expect->tuple.dst.protonum));
+       return seq_putc(s, '\n');
+}
+
+static struct seq_operations exp_seq_ops = {
+       .start = exp_seq_start,
+       .next = exp_seq_next,
+       .stop = exp_seq_stop,
+       .show = exp_seq_show
+};
+
+static int exp_open(struct inode *inode, struct file *file)
+{
+       return seq_open(file, &exp_seq_ops);
+}
+
+struct file_operations exp_file_ops = {
+       .owner   = THIS_MODULE,
+       .open    = exp_open,
+       .read    = seq_read,
+       .llseek  = seq_lseek,
+       .release = seq_release
+};
+#endif /* CONFIG_PROC_FS */
index 0c17a5bd112bb1792d32bffe662ece19d2987584..503fabf18843ea24ab0a354ae3f4e1ca0bde3cba 100644 (file)
@@ -26,6 +26,7 @@
 #include <net/tcp.h>
 
 #include <net/netfilter/nf_conntrack.h>
+#include <net/netfilter/nf_conntrack_expect.h>
 #include <net/netfilter/nf_conntrack_helper.h>
 #include <linux/netfilter/nf_conntrack_ftp.h>
 
index cfb35fd8d9b9bdace28ade1d52997a28f078c521..c3d53d91929f76be5cd6dfe62da959f65742ab1e 100644 (file)
@@ -35,6 +35,7 @@
 #include <linux/netfilter.h>
 #include <net/netfilter/nf_conntrack.h>
 #include <net/netfilter/nf_conntrack_core.h>
+#include <net/netfilter/nf_conntrack_expect.h>
 #include <net/netfilter/nf_conntrack_helper.h>
 #include <net/netfilter/nf_conntrack_l3proto.h>
 #include <net/netfilter/nf_conntrack_protocol.h>
index 5954f6773810591e96fffaae245b1a40bf8fdf2d..72643d32cab3eda6d5f8b0c790abcb5a2946d090 100644 (file)
@@ -36,6 +36,7 @@
 #include <net/netfilter/nf_conntrack_l3proto.h>
 #include <net/netfilter/nf_conntrack_protocol.h>
 #include <net/netfilter/nf_conntrack_core.h>
+#include <net/netfilter/nf_conntrack_expect.h>
 #include <net/netfilter/nf_conntrack_helper.h>
 
 #if 0
@@ -66,7 +67,7 @@ static int kill_proto(struct nf_conn *i, void *data)
 }
 
 #ifdef CONFIG_PROC_FS
-static int
+int
 print_tuple(struct seq_file *s, const struct nf_conntrack_tuple *tuple,
            struct nf_conntrack_l3proto *l3proto,
            struct nf_conntrack_protocol *proto)
@@ -258,84 +259,6 @@ static struct file_operations ct_file_ops = {
        .release = seq_release_private,
 };
 
-/* expects */
-static void *exp_seq_start(struct seq_file *s, loff_t *pos)
-{
-       struct list_head *e = &nf_conntrack_expect_list;
-       loff_t i;
-
-       /* strange seq_file api calls stop even if we fail,
-        * thus we need to grab lock since stop unlocks */
-       read_lock_bh(&nf_conntrack_lock);
-
-       if (list_empty(e))
-               return NULL;
-
-       for (i = 0; i <= *pos; i++) {
-               e = e->next;
-               if (e == &nf_conntrack_expect_list)
-                       return NULL;
-       }
-       return e;
-}
-
-static void *exp_seq_next(struct seq_file *s, void *v, loff_t *pos)
-{
-       struct list_head *e = v;
-
-       ++*pos;
-       e = e->next;
-
-       if (e == &nf_conntrack_expect_list)
-               return NULL;
-
-       return e;
-}
-
-static void exp_seq_stop(struct seq_file *s, void *v)
-{
-       read_unlock_bh(&nf_conntrack_lock);
-}
-
-static int exp_seq_show(struct seq_file *s, void *v)
-{
-       struct nf_conntrack_expect *expect = v;
-
-       if (expect->timeout.function)
-               seq_printf(s, "%ld ", timer_pending(&expect->timeout)
-                          ? (long)(expect->timeout.expires - jiffies)/HZ : 0);
-       else
-               seq_printf(s, "- ");
-       seq_printf(s, "l3proto = %u proto=%u ",
-                  expect->tuple.src.l3num,
-                  expect->tuple.dst.protonum);
-       print_tuple(s, &expect->tuple,
-                   __nf_ct_l3proto_find(expect->tuple.src.l3num),
-                   __nf_ct_proto_find(expect->tuple.src.l3num,
-                                      expect->tuple.dst.protonum));
-       return seq_putc(s, '\n');
-}
-
-static struct seq_operations exp_seq_ops = {
-       .start = exp_seq_start,
-       .next = exp_seq_next,
-       .stop = exp_seq_stop,
-       .show = exp_seq_show
-};
-
-static int exp_open(struct inode *inode, struct file *file)
-{
-       return seq_open(file, &exp_seq_ops);
-}
-
-static struct file_operations exp_file_ops = {
-       .owner   = THIS_MODULE,
-       .open    = exp_open,
-       .read    = seq_read,
-       .llseek  = seq_lseek,
-       .release = seq_release
-};
-
 static void *ct_cpu_seq_start(struct seq_file *seq, loff_t *pos)
 {
        int cpu;