]> err.no Git - linux-2.6/blobdiff - net/netfilter/nf_conntrack_core.c
[NETFILTER]: nf_conntrack: split out protocol handling
[linux-2.6] / net / netfilter / nf_conntrack_core.c
index 836541e509fe14e67e04c10012b94ae594c0446b..09c0e63110443ccc6358c2255dff3b9006830708 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>
 
@@ -72,87 +73,15 @@ 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);
+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);
-
-DEFINE_PER_CPU(struct nf_conntrack_ecache, nf_conntrack_ecache);
-
-/* deliver cached events and clear cache entry - must be called with locally
- * disabled softirqs */
-static inline void
-__nf_ct_deliver_cached_events(struct nf_conntrack_ecache *ecache)
-{
-       DEBUGP("ecache: delivering events for %p\n", ecache->ct);
-       if (nf_ct_is_confirmed(ecache->ct) && !nf_ct_is_dying(ecache->ct)
-           && ecache->events)
-               atomic_notifier_call_chain(&nf_conntrack_chain, ecache->events,
-                                   ecache->ct);
-
-       ecache->events = 0;
-       nf_ct_put(ecache->ct);
-       ecache->ct = NULL;
-}
-
-/* Deliver all cached events for a particular conntrack. This is called
- * by code prior to async packet handling for freeing the skb */
-void nf_ct_deliver_cached_events(const struct nf_conn *ct)
-{
-       struct nf_conntrack_ecache *ecache;
-
-       local_bh_disable();
-       ecache = &__get_cpu_var(nf_conntrack_ecache);
-       if (ecache->ct == ct)
-               __nf_ct_deliver_cached_events(ecache);
-       local_bh_enable();
-}
-
-/* Deliver cached events for old pending events, if current conntrack != old */
-void __nf_ct_event_cache_init(struct nf_conn *ct)
-{
-       struct nf_conntrack_ecache *ecache;
-       
-       /* take care of delivering potentially old events */
-       ecache = &__get_cpu_var(nf_conntrack_ecache);
-       BUG_ON(ecache->ct == ct);
-       if (ecache->ct)
-               __nf_ct_deliver_cached_events(ecache);
-       /* initialize for this conntrack/packet */
-       ecache->ct = ct;
-       nf_conntrack_get(&ct->ct_general);
-}
-
-/* flush the event cache - touches other CPU's data and must not be called
- * while packets are still passing through the code */
-static void nf_ct_event_cache_flush(void)
-{
-       struct nf_conntrack_ecache *ecache;
-       int cpu;
-
-       for_each_possible_cpu(cpu) {
-               ecache = &per_cpu(nf_conntrack_ecache, cpu);
-               if (ecache->ct)
-                       nf_ct_put(ecache->ct);
-       }
-}
-#else
-static inline void nf_ct_event_cache_flush(void) {}
-#endif /* CONFIG_NF_CONNTRACK_EVENTS */
 
 DEFINE_PER_CPU(struct ip_conntrack_stat, nf_conntrack_stat);
 EXPORT_PER_CPU_SYMBOL(nf_conntrack_stat);
@@ -184,85 +113,6 @@ DEFINE_RWLOCK(nf_ct_cache_lock);
 /* This avoids calling kmem_cache_create() with same name simultaneously */
 static DEFINE_MUTEX(nf_ct_cache_mutex);
 
-extern struct nf_conntrack_protocol nf_conntrack_generic_protocol;
-struct nf_conntrack_protocol *
-__nf_ct_proto_find(u_int16_t l3proto, u_int8_t protocol)
-{
-       if (unlikely(l3proto >= AF_MAX || nf_ct_protos[l3proto] == NULL))
-               return &nf_conntrack_generic_protocol;
-
-       return nf_ct_protos[l3proto][protocol];
-}
-
-/* this is guaranteed to always return a valid protocol helper, since
- * it falls back to generic_protocol */
-struct nf_conntrack_protocol *
-nf_ct_proto_find_get(u_int16_t l3proto, u_int8_t protocol)
-{
-       struct nf_conntrack_protocol *p;
-
-       preempt_disable();
-       p = __nf_ct_proto_find(l3proto, protocol);
-       if (!try_module_get(p->me))
-               p = &nf_conntrack_generic_protocol;
-       preempt_enable();
-       
-       return p;
-}
-
-void nf_ct_proto_put(struct nf_conntrack_protocol *p)
-{
-       module_put(p->me);
-}
-
-struct nf_conntrack_l3proto *
-nf_ct_l3proto_find_get(u_int16_t l3proto)
-{
-       struct nf_conntrack_l3proto *p;
-
-       preempt_disable();
-       p = __nf_ct_l3proto_find(l3proto);
-       if (!try_module_get(p->me))
-               p = &nf_conntrack_generic_l3proto;
-       preempt_enable();
-
-       return p;
-}
-
-void nf_ct_l3proto_put(struct nf_conntrack_l3proto *p)
-{
-       module_put(p->me);
-}
-
-int
-nf_ct_l3proto_try_module_get(unsigned short l3proto)
-{
-       int ret;
-       struct nf_conntrack_l3proto *p;
-
-retry: p = nf_ct_l3proto_find_get(l3proto);
-       if (p == &nf_conntrack_generic_l3proto) {
-               ret = request_module("nf_conntrack-%d", l3proto);
-               if (!ret)
-                       goto retry;
-
-               return -EPROTOTYPE;
-       }
-
-       return 0;
-}
-
-void nf_ct_l3proto_module_put(unsigned short l3proto)
-{
-       struct nf_conntrack_l3proto *p;
-
-       preempt_disable();
-       p = __nf_ct_l3proto_find(l3proto);
-       preempt_enable();
-
-       module_put(p->me);
-}
-
 static int nf_conntrack_hash_rnd_initted;
 static unsigned int nf_conntrack_hash_rnd;
 
@@ -438,103 +288,6 @@ 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)) {
-                       atomic_inc(&i->use);
-                       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);
-       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)
 {
@@ -794,46 +547,6 @@ 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,
@@ -893,12 +606,6 @@ __nf_conntrack_alloc(const struct nf_conntrack_tuple *orig,
 
        memset(conntrack, 0, nf_ct_cache[features].size);
        conntrack->features = features;
-       if (helper) {
-               struct nf_conn_help *help = nfct_help(conntrack);
-               NF_CT_ASSERT(help);
-               help->helper = helper;
-       }
-
        atomic_set(&conntrack->ct_general.use, 1);
        conntrack->ct_general.destroy = destroy_conntrack;
        conntrack->tuplehash[IP_CT_DIR_ORIGINAL].tuple = *orig;
@@ -982,8 +689,13 @@ init_conntrack(const struct nf_conntrack_tuple *tuple,
 #endif
                nf_conntrack_get(&conntrack->master->ct_general);
                NF_CT_STAT_INC(expect_new);
-       } else
+       } else {
+               struct nf_conn_help *help = nfct_help(conntrack);
+
+               if (help)
+                       help->helper = __nf_ct_helper_find(&repl_tuple);
                NF_CT_STAT_INC(new);
+       }
 
        /* Overload tuple linked list to put us in unconfirmed list. */
        list_add(&conntrack->tuplehash[IP_CT_DIR_ORIGINAL].list, &unconfirmed);
@@ -1134,246 +846,6 @@ 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;
-       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,