extension. */
/* (C) 1999-2001 Paul `Rusty' Russell
- * (C) 2002-2005 Netfilter Core Team <coreteam@netfilter.org>
+ * (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
* - generalize L3 protocol denendent part.
* 23 Mar 2004: Yasuyuki Kozakai @USAGI <yasuyuki.kozakai@toshiba.co.jp>
* - add support various size of conntrack structures.
+ * 26 Jan 2006: Harald Welte <laforge@netfilter.org>
+ * - restructure nf_conn (introduce nf_conn_help)
+ * - redesign 'features' how they were originally intended
+ * 26 Feb 2006: Pablo Neira Ayuso <pablo@eurodev.net>
+ * - add support for L3 protocol module load on demand.
*
* Derived from net/ipv4/netfilter/ip_conntrack_core.c
*/
#include <net/netfilter/nf_conntrack_core.h>
#include <linux/netfilter_ipv4/listhelp.h>
-#define NF_CONNTRACK_VERSION "0.4.1"
+#define NF_CONNTRACK_VERSION "0.5.0"
#if 0
#define DEBUGP printk
static LIST_HEAD(unconfirmed);
static int nf_conntrack_vmalloc;
-static unsigned int nf_conntrack_next_id = 1;
-static unsigned int nf_conntrack_expect_next_id = 1;
+static unsigned int nf_conntrack_next_id;
+static unsigned int nf_conntrack_expect_next_id;
#ifdef CONFIG_NF_CONNTRACK_EVENTS
-struct notifier_block *nf_conntrack_chain;
-struct notifier_block *nf_conntrack_expect_chain;
+ATOMIC_NOTIFIER_HEAD(nf_conntrack_chain);
+ATOMIC_NOTIFIER_HEAD(nf_conntrack_expect_chain);
DEFINE_PER_CPU(struct nf_conntrack_ecache, nf_conntrack_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)
- notifier_call_chain(&nf_conntrack_chain, ecache->events,
+ atomic_notifier_call_chain(&nf_conntrack_chain, ecache->events,
ecache->ct);
ecache->events = 0;
struct nf_conntrack_ecache *ecache;
int cpu;
- for_each_cpu(cpu) {
+ for_each_possible_cpu(cpu) {
ecache = &per_cpu(nf_conntrack_ecache, cpu);
if (ecache->ct)
nf_ct_put(ecache->ct);
/* allocated slab cache + modules which uses this slab cache */
int use;
- /* Initialization */
- int (*init_conntrack)(struct nf_conn *, u_int32_t);
-
} nf_ct_cache[NF_CT_F_NUM];
/* protect members of nf_ct_cache except of "use" */
DEFINE_RWLOCK(nf_ct_cache_lock);
/* This avoids calling kmem_cache_create() with same name simultaneously */
-DECLARE_MUTEX(nf_ct_cache_mutex);
+static DEFINE_MUTEX(nf_ct_cache_mutex);
extern struct nf_conntrack_protocol nf_conntrack_generic_protocol;
struct nf_conntrack_protocol *
preempt_disable();
p = __nf_ct_proto_find(l3proto, protocol);
- if (p) {
- if (!try_module_get(p->me))
- p = &nf_conntrack_generic_protocol;
- }
+ if (!try_module_get(p->me))
+ p = &nf_conntrack_generic_protocol;
preempt_enable();
return p;
preempt_disable();
p = __nf_ct_l3proto_find(l3proto);
- if (p) {
- if (!try_module_get(p->me))
- p = &nf_conntrack_generic_l3proto;
- }
+ if (!try_module_get(p->me))
+ p = &nf_conntrack_generic_l3proto;
preempt_enable();
return 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;
nf_conntrack_hash_rnd);
}
-/* Initialize "struct nf_conn" which has spaces for helper */
-static int
-init_conntrack_for_helper(struct nf_conn *conntrack, u_int32_t features)
-{
-
- conntrack->help = (union nf_conntrack_help *)
- (((unsigned long)conntrack->data
- + (__alignof__(union nf_conntrack_help) - 1))
- & (~((unsigned long)(__alignof__(union nf_conntrack_help) -1))));
- return 0;
-}
-
int nf_conntrack_register_cache(u_int32_t features, const char *name,
- size_t size,
- int (*init)(struct nf_conn *, u_int32_t))
+ size_t size)
{
int ret = 0;
char *cache_name;
return -EINVAL;
}
- down(&nf_ct_cache_mutex);
+ mutex_lock(&nf_ct_cache_mutex);
write_lock_bh(&nf_ct_cache_lock);
/* e.g: multiple helpers are loaded */
DEBUGP("nf_conntrack_register_cache: already resisterd.\n");
if ((!strncmp(nf_ct_cache[features].name, name,
NF_CT_FEATURES_NAMELEN))
- && nf_ct_cache[features].size == size
- && nf_ct_cache[features].init_conntrack == init) {
+ && nf_ct_cache[features].size == size) {
DEBUGP("nf_conntrack_register_cache: reusing.\n");
nf_ct_cache[features].use++;
ret = 0;
ret = -EBUSY;
write_unlock_bh(&nf_ct_cache_lock);
- up(&nf_ct_cache_mutex);
+ mutex_unlock(&nf_ct_cache_mutex);
return ret;
}
write_unlock_bh(&nf_ct_cache_lock);
write_lock_bh(&nf_ct_cache_lock);
nf_ct_cache[features].use = 1;
nf_ct_cache[features].size = size;
- nf_ct_cache[features].init_conntrack = init;
nf_ct_cache[features].cachep = cachep;
nf_ct_cache[features].name = cache_name;
write_unlock_bh(&nf_ct_cache_lock);
out_free_name:
kfree(cache_name);
out_up_mutex:
- up(&nf_ct_cache_mutex);
+ mutex_unlock(&nf_ct_cache_mutex);
return ret;
}
* slab cache.
*/
DEBUGP("nf_conntrack_unregister_cache: 0x%04x\n", features);
- down(&nf_ct_cache_mutex);
+ mutex_lock(&nf_ct_cache_mutex);
write_lock_bh(&nf_ct_cache_lock);
if (--nf_ct_cache[features].use > 0) {
write_unlock_bh(&nf_ct_cache_lock);
- up(&nf_ct_cache_mutex);
+ mutex_unlock(&nf_ct_cache_mutex);
return;
}
cachep = nf_ct_cache[features].cachep;
name = nf_ct_cache[features].name;
nf_ct_cache[features].cachep = NULL;
nf_ct_cache[features].name = NULL;
- nf_ct_cache[features].init_conntrack = NULL;
nf_ct_cache[features].size = 0;
write_unlock_bh(&nf_ct_cache_lock);
kmem_cache_destroy(cachep);
kfree(name);
- up(&nf_ct_cache_mutex);
+ mutex_unlock(&nf_ct_cache_mutex);
}
int
/* 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);
- exp->master->expecting--;
+ master_help->expecting--;
nf_conntrack_expect_put(exp);
}
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 (ct->expecting == 0)
+ if (!help || help->expecting == 0)
return;
list_for_each_entry_safe(i, tmp, &nf_conntrack_expect_list, list) {
conntrack_tuple_cmp,
struct nf_conntrack_tuple_hash *,
&ct->tuplehash[IP_CT_DIR_REPLY].tuple, NULL)) {
+ struct nf_conn_help *help;
/* Remove from unconfirmed list */
list_del(&ct->tuplehash[IP_CT_DIR_ORIGINAL].list);
set_bit(IPS_CONFIRMED_BIT, &ct->status);
NF_CT_STAT_INC(insert);
write_unlock_bh(&nf_conntrack_lock);
- if (ct->helper)
+ help = nfct_help(ct);
+ if (help && help->helper)
nf_conntrack_event_cache(IPCT_HELPER, *pskb);
#ifdef CONFIG_NF_NAT_NEEDED
if (test_bit(IPS_SRC_NAT_DONE_BIT, &ct->status) ||
{
struct nf_conn *conntrack = NULL;
u_int32_t features = 0;
+ struct nf_conntrack_helper *helper;
- if (!nf_conntrack_hash_rnd_initted) {
+ if (unlikely(!nf_conntrack_hash_rnd_initted)) {
get_random_bytes(&nf_conntrack_hash_rnd, 4);
nf_conntrack_hash_rnd_initted = 1;
}
/* find features needed by this conntrack. */
features = l3proto->get_features(orig);
+
+ /* FIXME: protect helper list per RCU */
read_lock_bh(&nf_conntrack_lock);
- if (__nf_ct_helper_find(repl) != NULL)
+ helper = __nf_ct_helper_find(repl);
+ if (helper)
features |= NF_CT_F_HELP;
read_unlock_bh(&nf_conntrack_lock);
read_lock_bh(&nf_ct_cache_lock);
- if (!nf_ct_cache[features].use) {
+ if (unlikely(!nf_ct_cache[features].use)) {
DEBUGP("nf_conntrack_alloc: not supported features = 0x%x\n",
features);
goto out;
memset(conntrack, 0, nf_ct_cache[features].size);
conntrack->features = features;
- if (nf_ct_cache[features].init_conntrack &&
- nf_ct_cache[features].init_conntrack(conntrack, features) < 0) {
- DEBUGP("nf_conntrack_alloc: failed to init\n");
- kmem_cache_free(nf_ct_cache[features].cachep, conntrack);
- conntrack = NULL;
- goto out;
+ 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->master = exp->master;
#ifdef CONFIG_NF_CONNTRACK_MARK
conntrack->mark = exp->master->mark;
+#endif
+#ifdef CONFIG_NF_CONNTRACK_SECMARK
+ conntrack->secmark = exp->master->secmark;
#endif
nf_conntrack_get(&conntrack->master->ct_general);
NF_CT_STAT_INC(expect_new);
- } else {
- conntrack->helper = __nf_ct_helper_find(&repl_tuple);
-
+ } else
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);
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);
- exp->master->expecting++;
+ 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 + exp->master->helper->timeout * HZ;
+ exp->timeout.expires = jiffies + master_help->helper->timeout * HZ;
add_timer(&exp->timeout);
exp->id = ++nf_conntrack_expect_next_id;
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 + i->master->helper->timeout*HZ;
+ i->timeout.expires = jiffies + master_help->helper->timeout*HZ;
add_timer(&i->timeout);
return 1;
}
{
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);
}
}
/* Will be over limit? */
- if (master->helper->max_expected &&
- master->expecting >= master->helper->max_expected)
+ if (master_help->helper->max_expected &&
+ master_help->expecting >= master_help->helper->max_expected)
evict_oldest_expect(master);
nf_conntrack_expect_insert(expect);
return ret;
}
-/* Alter reply tuple (maybe alter helper). This is for NAT, and is
- implicitly racy: see __nf_conntrack_confirm */
-void nf_conntrack_alter_reply(struct nf_conn *conntrack,
- const struct nf_conntrack_tuple *newreply)
-{
- write_lock_bh(&nf_conntrack_lock);
- /* Should be unconfirmed, so not in hash table yet */
- NF_CT_ASSERT(!nf_ct_is_confirmed(conntrack));
-
- DEBUGP("Altering reply tuple of %p to ", conntrack);
- NF_CT_DUMP_TUPLE(newreply);
-
- conntrack->tuplehash[IP_CT_DIR_REPLY].tuple = *newreply;
- if (!conntrack->master && conntrack->expecting == 0)
- conntrack->helper = __nf_ct_helper_find(newreply);
- write_unlock_bh(&nf_conntrack_lock);
-}
-
int nf_conntrack_helper_register(struct nf_conntrack_helper *me)
{
int ret;
ret = nf_conntrack_register_cache(NF_CT_F_HELP, "nf_conntrack:help",
sizeof(struct nf_conn)
- + sizeof(union nf_conntrack_help)
- + __alignof__(union nf_conntrack_help),
- init_conntrack_for_helper);
+ + 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;
static inline int unhelp(struct nf_conntrack_tuple_hash *i,
const struct nf_conntrack_helper *me)
{
- if (nf_ct_tuplehash_to_ctrack(i)->helper == me) {
- nf_conntrack_event(IPCT_HELPER, nf_ct_tuplehash_to_ctrack(i));
- nf_ct_tuplehash_to_ctrack(i)->helper = NULL;
+ 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;
}
/* Get rid of expectations */
list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list, list) {
- if (exp->master->helper == me && del_timer(&exp->timeout)) {
+ 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);
}
write_lock_bh(&nf_conntrack_lock);
+ /* Only update if this is not a fixed timeout */
+ if (test_bit(IPS_FIXED_TIMEOUT_BIT, &ct->status)) {
+ write_unlock_bh(&nf_conntrack_lock);
+ return;
+ }
+
/* If not in hash table, timer will not be active yet */
if (!nf_ct_is_confirmed(ct)) {
ct->timeout.expires = extra_jiffies;
#include <linux/netfilter/nfnetlink.h>
#include <linux/netfilter/nfnetlink_conntrack.h>
+#include <linux/mutex.h>
+
/* Generic function for tcp/udp/sctp/dccp and alike. This needs to be
* in ip_conntrack_core, since we don't want the protocols to autoload
}
ret = nf_conntrack_register_cache(NF_CT_F_BASIC, "nf_conntrack:basic",
- sizeof(struct nf_conn), NULL);
+ sizeof(struct nf_conn));
if (ret < 0) {
printk(KERN_ERR "Unable to create nf_conn slab cache\n");
goto err_free_hash;