1165 lines
32 KiB
C
1165 lines
32 KiB
C
/* Connection state tracking for netfilter. This is separated from,
|
|
but required by, the NAT layer; it can also be used by an iptables
|
|
extension. */
|
|
|
|
/* (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/proc_fs.h>
|
|
#include <linux/vmalloc.h>
|
|
#include <linux/stddef.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/random.h>
|
|
#include <linux/jhash.h>
|
|
#include <linux/err.h>
|
|
#include <linux/percpu.h>
|
|
#include <linux/moduleparam.h>
|
|
#include <linux/notifier.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/netdevice.h>
|
|
#include <linux/socket.h>
|
|
#include <linux/mm.h>
|
|
|
|
#include <net/netfilter/nf_conntrack.h>
|
|
#include <net/netfilter/nf_conntrack_l3proto.h>
|
|
#include <net/netfilter/nf_conntrack_l4proto.h>
|
|
#include <net/netfilter/nf_conntrack_expect.h>
|
|
#include <net/netfilter/nf_conntrack_helper.h>
|
|
#include <net/netfilter/nf_conntrack_core.h>
|
|
#include <net/netfilter/nf_conntrack_extend.h>
|
|
|
|
#define NF_CONNTRACK_VERSION "0.5.0"
|
|
|
|
DEFINE_RWLOCK(nf_conntrack_lock);
|
|
EXPORT_SYMBOL_GPL(nf_conntrack_lock);
|
|
|
|
/* nf_conntrack_standalone needs this */
|
|
atomic_t nf_conntrack_count = ATOMIC_INIT(0);
|
|
EXPORT_SYMBOL_GPL(nf_conntrack_count);
|
|
|
|
unsigned int nf_conntrack_htable_size __read_mostly;
|
|
EXPORT_SYMBOL_GPL(nf_conntrack_htable_size);
|
|
|
|
int nf_conntrack_max __read_mostly;
|
|
EXPORT_SYMBOL_GPL(nf_conntrack_max);
|
|
|
|
struct hlist_head *nf_conntrack_hash __read_mostly;
|
|
EXPORT_SYMBOL_GPL(nf_conntrack_hash);
|
|
|
|
struct nf_conn nf_conntrack_untracked __read_mostly;
|
|
EXPORT_SYMBOL_GPL(nf_conntrack_untracked);
|
|
|
|
unsigned int nf_ct_log_invalid __read_mostly;
|
|
HLIST_HEAD(unconfirmed);
|
|
static int nf_conntrack_vmalloc __read_mostly;
|
|
static struct kmem_cache *nf_conntrack_cachep __read_mostly;
|
|
|
|
DEFINE_PER_CPU(struct ip_conntrack_stat, nf_conntrack_stat);
|
|
EXPORT_PER_CPU_SYMBOL(nf_conntrack_stat);
|
|
|
|
static int nf_conntrack_hash_rnd_initted;
|
|
static unsigned int nf_conntrack_hash_rnd;
|
|
|
|
static u_int32_t __hash_conntrack(const struct nf_conntrack_tuple *tuple,
|
|
unsigned int size, unsigned int rnd)
|
|
{
|
|
unsigned int a, b;
|
|
|
|
a = jhash2(tuple->src.u3.all, ARRAY_SIZE(tuple->src.u3.all),
|
|
(tuple->src.l3num << 16) | tuple->dst.protonum);
|
|
b = jhash2(tuple->dst.u3.all, ARRAY_SIZE(tuple->dst.u3.all),
|
|
((__force __u16)tuple->src.u.all << 16) |
|
|
(__force __u16)tuple->dst.u.all);
|
|
|
|
return ((u64)jhash_2words(a, b, rnd) * size) >> 32;
|
|
}
|
|
|
|
static inline u_int32_t hash_conntrack(const struct nf_conntrack_tuple *tuple)
|
|
{
|
|
return __hash_conntrack(tuple, nf_conntrack_htable_size,
|
|
nf_conntrack_hash_rnd);
|
|
}
|
|
|
|
int
|
|
nf_ct_get_tuple(const struct sk_buff *skb,
|
|
unsigned int nhoff,
|
|
unsigned int dataoff,
|
|
u_int16_t l3num,
|
|
u_int8_t protonum,
|
|
struct nf_conntrack_tuple *tuple,
|
|
const struct nf_conntrack_l3proto *l3proto,
|
|
const struct nf_conntrack_l4proto *l4proto)
|
|
{
|
|
NF_CT_TUPLE_U_BLANK(tuple);
|
|
|
|
tuple->src.l3num = l3num;
|
|
if (l3proto->pkt_to_tuple(skb, nhoff, tuple) == 0)
|
|
return 0;
|
|
|
|
tuple->dst.protonum = protonum;
|
|
tuple->dst.dir = IP_CT_DIR_ORIGINAL;
|
|
|
|
return l4proto->pkt_to_tuple(skb, dataoff, tuple);
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_ct_get_tuple);
|
|
|
|
int nf_ct_get_tuplepr(const struct sk_buff *skb,
|
|
unsigned int nhoff,
|
|
u_int16_t l3num,
|
|
struct nf_conntrack_tuple *tuple)
|
|
{
|
|
struct nf_conntrack_l3proto *l3proto;
|
|
struct nf_conntrack_l4proto *l4proto;
|
|
unsigned int protoff;
|
|
u_int8_t protonum;
|
|
int ret;
|
|
|
|
rcu_read_lock();
|
|
|
|
l3proto = __nf_ct_l3proto_find(l3num);
|
|
ret = l3proto->get_l4proto(skb, nhoff, &protoff, &protonum);
|
|
if (ret != NF_ACCEPT) {
|
|
rcu_read_unlock();
|
|
return 0;
|
|
}
|
|
|
|
l4proto = __nf_ct_l4proto_find(l3num, protonum);
|
|
|
|
ret = nf_ct_get_tuple(skb, nhoff, protoff, l3num, protonum, tuple,
|
|
l3proto, l4proto);
|
|
|
|
rcu_read_unlock();
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_ct_get_tuplepr);
|
|
|
|
int
|
|
nf_ct_invert_tuple(struct nf_conntrack_tuple *inverse,
|
|
const struct nf_conntrack_tuple *orig,
|
|
const struct nf_conntrack_l3proto *l3proto,
|
|
const struct nf_conntrack_l4proto *l4proto)
|
|
{
|
|
NF_CT_TUPLE_U_BLANK(inverse);
|
|
|
|
inverse->src.l3num = orig->src.l3num;
|
|
if (l3proto->invert_tuple(inverse, orig) == 0)
|
|
return 0;
|
|
|
|
inverse->dst.dir = !orig->dst.dir;
|
|
|
|
inverse->dst.protonum = orig->dst.protonum;
|
|
return l4proto->invert_tuple(inverse, orig);
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_ct_invert_tuple);
|
|
|
|
static void
|
|
clean_from_lists(struct nf_conn *ct)
|
|
{
|
|
pr_debug("clean_from_lists(%p)\n", ct);
|
|
hlist_del_rcu(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnode);
|
|
hlist_del_rcu(&ct->tuplehash[IP_CT_DIR_REPLY].hnode);
|
|
|
|
/* Destroy all pending expectations */
|
|
nf_ct_remove_expectations(ct);
|
|
}
|
|
|
|
static void
|
|
destroy_conntrack(struct nf_conntrack *nfct)
|
|
{
|
|
struct nf_conn *ct = (struct nf_conn *)nfct;
|
|
struct nf_conntrack_l4proto *l4proto;
|
|
|
|
pr_debug("destroy_conntrack(%p)\n", ct);
|
|
NF_CT_ASSERT(atomic_read(&nfct->use) == 0);
|
|
NF_CT_ASSERT(!timer_pending(&ct->timeout));
|
|
|
|
nf_conntrack_event(IPCT_DESTROY, ct);
|
|
set_bit(IPS_DYING_BIT, &ct->status);
|
|
|
|
/* To make sure we don't get any weird locking issues here:
|
|
* destroy_conntrack() MUST NOT be called with a write lock
|
|
* to nf_conntrack_lock!!! -HW */
|
|
rcu_read_lock();
|
|
l4proto = __nf_ct_l4proto_find(ct->tuplehash[IP_CT_DIR_REPLY].tuple.src.l3num,
|
|
ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.protonum);
|
|
if (l4proto && l4proto->destroy)
|
|
l4proto->destroy(ct);
|
|
|
|
nf_ct_ext_destroy(ct);
|
|
|
|
rcu_read_unlock();
|
|
|
|
write_lock_bh(&nf_conntrack_lock);
|
|
/* Expectations will have been removed in clean_from_lists,
|
|
* except TFTP can create an expectation on the first packet,
|
|
* before connection is in the list, so we need to clean here,
|
|
* too. */
|
|
nf_ct_remove_expectations(ct);
|
|
|
|
/* We overload first tuple to link into unconfirmed list. */
|
|
if (!nf_ct_is_confirmed(ct)) {
|
|
BUG_ON(hlist_unhashed(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnode));
|
|
hlist_del(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnode);
|
|
}
|
|
|
|
NF_CT_STAT_INC(delete);
|
|
write_unlock_bh(&nf_conntrack_lock);
|
|
|
|
if (ct->master)
|
|
nf_ct_put(ct->master);
|
|
|
|
pr_debug("destroy_conntrack: returning ct=%p to slab\n", ct);
|
|
nf_conntrack_free(ct);
|
|
}
|
|
|
|
static void death_by_timeout(unsigned long ul_conntrack)
|
|
{
|
|
struct nf_conn *ct = (void *)ul_conntrack;
|
|
struct nf_conn_help *help = nfct_help(ct);
|
|
struct nf_conntrack_helper *helper;
|
|
|
|
if (help) {
|
|
rcu_read_lock();
|
|
helper = rcu_dereference(help->helper);
|
|
if (helper && helper->destroy)
|
|
helper->destroy(ct);
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
write_lock_bh(&nf_conntrack_lock);
|
|
/* Inside lock so preempt is disabled on module removal path.
|
|
* Otherwise we can get spurious warnings. */
|
|
NF_CT_STAT_INC(delete_list);
|
|
clean_from_lists(ct);
|
|
write_unlock_bh(&nf_conntrack_lock);
|
|
nf_ct_put(ct);
|
|
}
|
|
|
|
struct nf_conntrack_tuple_hash *
|
|
__nf_conntrack_find(const struct nf_conntrack_tuple *tuple,
|
|
const struct nf_conn *ignored_conntrack)
|
|
{
|
|
struct nf_conntrack_tuple_hash *h;
|
|
struct hlist_node *n;
|
|
unsigned int hash = hash_conntrack(tuple);
|
|
|
|
hlist_for_each_entry_rcu(h, n, &nf_conntrack_hash[hash], hnode) {
|
|
if (nf_ct_tuplehash_to_ctrack(h) != ignored_conntrack &&
|
|
nf_ct_tuple_equal(tuple, &h->tuple)) {
|
|
NF_CT_STAT_INC(found);
|
|
return h;
|
|
}
|
|
NF_CT_STAT_INC(searched);
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
EXPORT_SYMBOL_GPL(__nf_conntrack_find);
|
|
|
|
/* Find a connection corresponding to a tuple. */
|
|
struct nf_conntrack_tuple_hash *
|
|
nf_conntrack_find_get(const struct nf_conntrack_tuple *tuple)
|
|
{
|
|
struct nf_conntrack_tuple_hash *h;
|
|
struct nf_conn *ct;
|
|
|
|
rcu_read_lock();
|
|
h = __nf_conntrack_find(tuple, NULL);
|
|
if (h) {
|
|
ct = nf_ct_tuplehash_to_ctrack(h);
|
|
if (unlikely(!atomic_inc_not_zero(&ct->ct_general.use)))
|
|
h = NULL;
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
return h;
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_conntrack_find_get);
|
|
|
|
static void __nf_conntrack_hash_insert(struct nf_conn *ct,
|
|
unsigned int hash,
|
|
unsigned int repl_hash)
|
|
{
|
|
hlist_add_head_rcu(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnode,
|
|
&nf_conntrack_hash[hash]);
|
|
hlist_add_head_rcu(&ct->tuplehash[IP_CT_DIR_REPLY].hnode,
|
|
&nf_conntrack_hash[repl_hash]);
|
|
}
|
|
|
|
void nf_conntrack_hash_insert(struct nf_conn *ct)
|
|
{
|
|
unsigned int hash, repl_hash;
|
|
|
|
hash = hash_conntrack(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
|
|
repl_hash = hash_conntrack(&ct->tuplehash[IP_CT_DIR_REPLY].tuple);
|
|
|
|
write_lock_bh(&nf_conntrack_lock);
|
|
__nf_conntrack_hash_insert(ct, hash, repl_hash);
|
|
write_unlock_bh(&nf_conntrack_lock);
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_conntrack_hash_insert);
|
|
|
|
/* Confirm a connection given skb; places it in hash table */
|
|
int
|
|
__nf_conntrack_confirm(struct sk_buff *skb)
|
|
{
|
|
unsigned int hash, repl_hash;
|
|
struct nf_conntrack_tuple_hash *h;
|
|
struct nf_conn *ct;
|
|
struct nf_conn_help *help;
|
|
struct hlist_node *n;
|
|
enum ip_conntrack_info ctinfo;
|
|
|
|
ct = nf_ct_get(skb, &ctinfo);
|
|
|
|
/* ipt_REJECT uses nf_conntrack_attach to attach related
|
|
ICMP/TCP RST packets in other direction. Actual packet
|
|
which created connection will be IP_CT_NEW or for an
|
|
expected connection, IP_CT_RELATED. */
|
|
if (CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL)
|
|
return NF_ACCEPT;
|
|
|
|
hash = hash_conntrack(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
|
|
repl_hash = hash_conntrack(&ct->tuplehash[IP_CT_DIR_REPLY].tuple);
|
|
|
|
/* We're not in hash table, and we refuse to set up related
|
|
connections for unconfirmed conns. But packet copies and
|
|
REJECT will give spurious warnings here. */
|
|
/* NF_CT_ASSERT(atomic_read(&ct->ct_general.use) == 1); */
|
|
|
|
/* No external references means noone else could have
|
|
confirmed us. */
|
|
NF_CT_ASSERT(!nf_ct_is_confirmed(ct));
|
|
pr_debug("Confirming conntrack %p\n", ct);
|
|
|
|
write_lock_bh(&nf_conntrack_lock);
|
|
|
|
/* See if there's one in the list already, including reverse:
|
|
NAT could have grabbed it without realizing, since we're
|
|
not in the hash. If there is, we lost race. */
|
|
hlist_for_each_entry(h, n, &nf_conntrack_hash[hash], hnode)
|
|
if (nf_ct_tuple_equal(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
|
|
&h->tuple))
|
|
goto out;
|
|
hlist_for_each_entry(h, n, &nf_conntrack_hash[repl_hash], hnode)
|
|
if (nf_ct_tuple_equal(&ct->tuplehash[IP_CT_DIR_REPLY].tuple,
|
|
&h->tuple))
|
|
goto out;
|
|
|
|
/* Remove from unconfirmed list */
|
|
hlist_del(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnode);
|
|
|
|
__nf_conntrack_hash_insert(ct, hash, repl_hash);
|
|
/* Timer relative to confirmation time, not original
|
|
setting time, otherwise we'd get timer wrap in
|
|
weird delay cases. */
|
|
ct->timeout.expires += jiffies;
|
|
add_timer(&ct->timeout);
|
|
atomic_inc(&ct->ct_general.use);
|
|
set_bit(IPS_CONFIRMED_BIT, &ct->status);
|
|
NF_CT_STAT_INC(insert);
|
|
write_unlock_bh(&nf_conntrack_lock);
|
|
help = nfct_help(ct);
|
|
if (help && help->helper)
|
|
nf_conntrack_event_cache(IPCT_HELPER, skb);
|
|
#ifdef CONFIG_NF_NAT_NEEDED
|
|
if (test_bit(IPS_SRC_NAT_DONE_BIT, &ct->status) ||
|
|
test_bit(IPS_DST_NAT_DONE_BIT, &ct->status))
|
|
nf_conntrack_event_cache(IPCT_NATINFO, skb);
|
|
#endif
|
|
nf_conntrack_event_cache(master_ct(ct) ?
|
|
IPCT_RELATED : IPCT_NEW, skb);
|
|
return NF_ACCEPT;
|
|
|
|
out:
|
|
NF_CT_STAT_INC(insert_failed);
|
|
write_unlock_bh(&nf_conntrack_lock);
|
|
return NF_DROP;
|
|
}
|
|
EXPORT_SYMBOL_GPL(__nf_conntrack_confirm);
|
|
|
|
/* Returns true if a connection correspondings to the tuple (required
|
|
for NAT). */
|
|
int
|
|
nf_conntrack_tuple_taken(const struct nf_conntrack_tuple *tuple,
|
|
const struct nf_conn *ignored_conntrack)
|
|
{
|
|
struct nf_conntrack_tuple_hash *h;
|
|
|
|
rcu_read_lock();
|
|
h = __nf_conntrack_find(tuple, ignored_conntrack);
|
|
rcu_read_unlock();
|
|
|
|
return h != NULL;
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_conntrack_tuple_taken);
|
|
|
|
#define NF_CT_EVICTION_RANGE 8
|
|
|
|
/* There's a small race here where we may free a just-assured
|
|
connection. Too bad: we're in trouble anyway. */
|
|
static int early_drop(unsigned int hash)
|
|
{
|
|
/* Use oldest entry, which is roughly LRU */
|
|
struct nf_conntrack_tuple_hash *h;
|
|
struct nf_conn *ct = NULL, *tmp;
|
|
struct hlist_node *n;
|
|
unsigned int i, cnt = 0;
|
|
int dropped = 0;
|
|
|
|
rcu_read_lock();
|
|
for (i = 0; i < nf_conntrack_htable_size; i++) {
|
|
hlist_for_each_entry_rcu(h, n, &nf_conntrack_hash[hash],
|
|
hnode) {
|
|
tmp = nf_ct_tuplehash_to_ctrack(h);
|
|
if (!test_bit(IPS_ASSURED_BIT, &tmp->status))
|
|
ct = tmp;
|
|
cnt++;
|
|
}
|
|
|
|
if (ct && unlikely(!atomic_inc_not_zero(&ct->ct_general.use)))
|
|
ct = NULL;
|
|
if (ct || cnt >= NF_CT_EVICTION_RANGE)
|
|
break;
|
|
hash = (hash + 1) % nf_conntrack_htable_size;
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
if (!ct)
|
|
return dropped;
|
|
|
|
if (del_timer(&ct->timeout)) {
|
|
death_by_timeout((unsigned long)ct);
|
|
dropped = 1;
|
|
NF_CT_STAT_INC_ATOMIC(early_drop);
|
|
}
|
|
nf_ct_put(ct);
|
|
return dropped;
|
|
}
|
|
|
|
struct nf_conn *nf_conntrack_alloc(const struct nf_conntrack_tuple *orig,
|
|
const struct nf_conntrack_tuple *repl)
|
|
{
|
|
struct nf_conn *conntrack = NULL;
|
|
|
|
if (unlikely(!nf_conntrack_hash_rnd_initted)) {
|
|
get_random_bytes(&nf_conntrack_hash_rnd, 4);
|
|
nf_conntrack_hash_rnd_initted = 1;
|
|
}
|
|
|
|
/* We don't want any race condition at early drop stage */
|
|
atomic_inc(&nf_conntrack_count);
|
|
|
|
if (nf_conntrack_max
|
|
&& atomic_read(&nf_conntrack_count) > nf_conntrack_max) {
|
|
unsigned int hash = hash_conntrack(orig);
|
|
if (!early_drop(hash)) {
|
|
atomic_dec(&nf_conntrack_count);
|
|
if (net_ratelimit())
|
|
printk(KERN_WARNING
|
|
"nf_conntrack: table full, dropping"
|
|
" packet.\n");
|
|
return ERR_PTR(-ENOMEM);
|
|
}
|
|
}
|
|
|
|
conntrack = kmem_cache_zalloc(nf_conntrack_cachep, GFP_ATOMIC);
|
|
if (conntrack == NULL) {
|
|
pr_debug("nf_conntrack_alloc: Can't alloc conntrack.\n");
|
|
atomic_dec(&nf_conntrack_count);
|
|
return ERR_PTR(-ENOMEM);
|
|
}
|
|
|
|
atomic_set(&conntrack->ct_general.use, 1);
|
|
conntrack->tuplehash[IP_CT_DIR_ORIGINAL].tuple = *orig;
|
|
conntrack->tuplehash[IP_CT_DIR_REPLY].tuple = *repl;
|
|
/* Don't set timer yet: wait for confirmation */
|
|
setup_timer(&conntrack->timeout, death_by_timeout,
|
|
(unsigned long)conntrack);
|
|
INIT_RCU_HEAD(&conntrack->rcu);
|
|
|
|
return conntrack;
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_conntrack_alloc);
|
|
|
|
static void nf_conntrack_free_rcu(struct rcu_head *head)
|
|
{
|
|
struct nf_conn *ct = container_of(head, struct nf_conn, rcu);
|
|
|
|
nf_ct_ext_free(ct);
|
|
kmem_cache_free(nf_conntrack_cachep, ct);
|
|
atomic_dec(&nf_conntrack_count);
|
|
}
|
|
|
|
void nf_conntrack_free(struct nf_conn *conntrack)
|
|
{
|
|
call_rcu(&conntrack->rcu, nf_conntrack_free_rcu);
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_conntrack_free);
|
|
|
|
/* Allocate a new conntrack: we return -ENOMEM if classification
|
|
failed due to stress. Otherwise it really is unclassifiable. */
|
|
static struct nf_conntrack_tuple_hash *
|
|
init_conntrack(const struct nf_conntrack_tuple *tuple,
|
|
struct nf_conntrack_l3proto *l3proto,
|
|
struct nf_conntrack_l4proto *l4proto,
|
|
struct sk_buff *skb,
|
|
unsigned int dataoff)
|
|
{
|
|
struct nf_conn *conntrack;
|
|
struct nf_conn_help *help;
|
|
struct nf_conntrack_tuple repl_tuple;
|
|
struct nf_conntrack_expect *exp;
|
|
|
|
if (!nf_ct_invert_tuple(&repl_tuple, tuple, l3proto, l4proto)) {
|
|
pr_debug("Can't invert tuple.\n");
|
|
return NULL;
|
|
}
|
|
|
|
conntrack = nf_conntrack_alloc(tuple, &repl_tuple);
|
|
if (conntrack == NULL || IS_ERR(conntrack)) {
|
|
pr_debug("Can't allocate conntrack.\n");
|
|
return (struct nf_conntrack_tuple_hash *)conntrack;
|
|
}
|
|
|
|
if (!l4proto->new(conntrack, skb, dataoff)) {
|
|
nf_conntrack_free(conntrack);
|
|
pr_debug("init conntrack: can't track with proto module\n");
|
|
return NULL;
|
|
}
|
|
|
|
write_lock_bh(&nf_conntrack_lock);
|
|
exp = nf_ct_find_expectation(tuple);
|
|
if (exp) {
|
|
pr_debug("conntrack: expectation arrives ct=%p exp=%p\n",
|
|
conntrack, exp);
|
|
/* Welcome, Mr. Bond. We've been expecting you... */
|
|
__set_bit(IPS_EXPECTED_BIT, &conntrack->status);
|
|
conntrack->master = exp->master;
|
|
if (exp->helper) {
|
|
help = nf_ct_helper_ext_add(conntrack, GFP_ATOMIC);
|
|
if (help)
|
|
rcu_assign_pointer(help->helper, exp->helper);
|
|
}
|
|
|
|
#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 {
|
|
struct nf_conntrack_helper *helper;
|
|
|
|
helper = __nf_ct_helper_find(&repl_tuple);
|
|
if (helper) {
|
|
help = nf_ct_helper_ext_add(conntrack, GFP_ATOMIC);
|
|
if (help)
|
|
rcu_assign_pointer(help->helper, helper);
|
|
}
|
|
NF_CT_STAT_INC(new);
|
|
}
|
|
|
|
/* Overload tuple linked list to put us in unconfirmed list. */
|
|
hlist_add_head(&conntrack->tuplehash[IP_CT_DIR_ORIGINAL].hnode,
|
|
&unconfirmed);
|
|
|
|
write_unlock_bh(&nf_conntrack_lock);
|
|
|
|
if (exp) {
|
|
if (exp->expectfn)
|
|
exp->expectfn(conntrack, exp);
|
|
nf_ct_expect_put(exp);
|
|
}
|
|
|
|
return &conntrack->tuplehash[IP_CT_DIR_ORIGINAL];
|
|
}
|
|
|
|
/* On success, returns conntrack ptr, sets skb->nfct and ctinfo */
|
|
static inline struct nf_conn *
|
|
resolve_normal_ct(struct sk_buff *skb,
|
|
unsigned int dataoff,
|
|
u_int16_t l3num,
|
|
u_int8_t protonum,
|
|
struct nf_conntrack_l3proto *l3proto,
|
|
struct nf_conntrack_l4proto *l4proto,
|
|
int *set_reply,
|
|
enum ip_conntrack_info *ctinfo)
|
|
{
|
|
struct nf_conntrack_tuple tuple;
|
|
struct nf_conntrack_tuple_hash *h;
|
|
struct nf_conn *ct;
|
|
|
|
if (!nf_ct_get_tuple(skb, skb_network_offset(skb),
|
|
dataoff, l3num, protonum, &tuple, l3proto,
|
|
l4proto)) {
|
|
pr_debug("resolve_normal_ct: Can't get tuple\n");
|
|
return NULL;
|
|
}
|
|
|
|
/* look for tuple match */
|
|
h = nf_conntrack_find_get(&tuple);
|
|
if (!h) {
|
|
h = init_conntrack(&tuple, l3proto, l4proto, skb, dataoff);
|
|
if (!h)
|
|
return NULL;
|
|
if (IS_ERR(h))
|
|
return (void *)h;
|
|
}
|
|
ct = nf_ct_tuplehash_to_ctrack(h);
|
|
|
|
/* It exists; we have (non-exclusive) reference. */
|
|
if (NF_CT_DIRECTION(h) == IP_CT_DIR_REPLY) {
|
|
*ctinfo = IP_CT_ESTABLISHED + IP_CT_IS_REPLY;
|
|
/* Please set reply bit if this packet OK */
|
|
*set_reply = 1;
|
|
} else {
|
|
/* Once we've had two way comms, always ESTABLISHED. */
|
|
if (test_bit(IPS_SEEN_REPLY_BIT, &ct->status)) {
|
|
pr_debug("nf_conntrack_in: normal packet for %p\n", ct);
|
|
*ctinfo = IP_CT_ESTABLISHED;
|
|
} else if (test_bit(IPS_EXPECTED_BIT, &ct->status)) {
|
|
pr_debug("nf_conntrack_in: related packet for %p\n",
|
|
ct);
|
|
*ctinfo = IP_CT_RELATED;
|
|
} else {
|
|
pr_debug("nf_conntrack_in: new packet for %p\n", ct);
|
|
*ctinfo = IP_CT_NEW;
|
|
}
|
|
*set_reply = 0;
|
|
}
|
|
skb->nfct = &ct->ct_general;
|
|
skb->nfctinfo = *ctinfo;
|
|
return ct;
|
|
}
|
|
|
|
unsigned int
|
|
nf_conntrack_in(int pf, unsigned int hooknum, struct sk_buff *skb)
|
|
{
|
|
struct nf_conn *ct;
|
|
enum ip_conntrack_info ctinfo;
|
|
struct nf_conntrack_l3proto *l3proto;
|
|
struct nf_conntrack_l4proto *l4proto;
|
|
unsigned int dataoff;
|
|
u_int8_t protonum;
|
|
int set_reply = 0;
|
|
int ret;
|
|
|
|
/* Previously seen (loopback or untracked)? Ignore. */
|
|
if (skb->nfct) {
|
|
NF_CT_STAT_INC_ATOMIC(ignore);
|
|
return NF_ACCEPT;
|
|
}
|
|
|
|
/* rcu_read_lock()ed by nf_hook_slow */
|
|
l3proto = __nf_ct_l3proto_find((u_int16_t)pf);
|
|
ret = l3proto->get_l4proto(skb, skb_network_offset(skb),
|
|
&dataoff, &protonum);
|
|
if (ret <= 0) {
|
|
pr_debug("not prepared to track yet or error occured\n");
|
|
NF_CT_STAT_INC_ATOMIC(error);
|
|
NF_CT_STAT_INC_ATOMIC(invalid);
|
|
return -ret;
|
|
}
|
|
|
|
l4proto = __nf_ct_l4proto_find((u_int16_t)pf, protonum);
|
|
|
|
/* It may be an special packet, error, unclean...
|
|
* inverse of the return code tells to the netfilter
|
|
* core what to do with the packet. */
|
|
if (l4proto->error != NULL &&
|
|
(ret = l4proto->error(skb, dataoff, &ctinfo, pf, hooknum)) <= 0) {
|
|
NF_CT_STAT_INC_ATOMIC(error);
|
|
NF_CT_STAT_INC_ATOMIC(invalid);
|
|
return -ret;
|
|
}
|
|
|
|
ct = resolve_normal_ct(skb, dataoff, pf, protonum, l3proto, l4proto,
|
|
&set_reply, &ctinfo);
|
|
if (!ct) {
|
|
/* Not valid part of a connection */
|
|
NF_CT_STAT_INC_ATOMIC(invalid);
|
|
return NF_ACCEPT;
|
|
}
|
|
|
|
if (IS_ERR(ct)) {
|
|
/* Too stressed to deal. */
|
|
NF_CT_STAT_INC_ATOMIC(drop);
|
|
return NF_DROP;
|
|
}
|
|
|
|
NF_CT_ASSERT(skb->nfct);
|
|
|
|
ret = l4proto->packet(ct, skb, dataoff, ctinfo, pf, hooknum);
|
|
if (ret < 0) {
|
|
/* Invalid: inverse of the return code tells
|
|
* the netfilter core what to do */
|
|
pr_debug("nf_conntrack_in: Can't track with proto module\n");
|
|
nf_conntrack_put(skb->nfct);
|
|
skb->nfct = NULL;
|
|
NF_CT_STAT_INC_ATOMIC(invalid);
|
|
return -ret;
|
|
}
|
|
|
|
if (set_reply && !test_and_set_bit(IPS_SEEN_REPLY_BIT, &ct->status))
|
|
nf_conntrack_event_cache(IPCT_STATUS, skb);
|
|
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_conntrack_in);
|
|
|
|
int nf_ct_invert_tuplepr(struct nf_conntrack_tuple *inverse,
|
|
const struct nf_conntrack_tuple *orig)
|
|
{
|
|
int ret;
|
|
|
|
rcu_read_lock();
|
|
ret = nf_ct_invert_tuple(inverse, orig,
|
|
__nf_ct_l3proto_find(orig->src.l3num),
|
|
__nf_ct_l4proto_find(orig->src.l3num,
|
|
orig->dst.protonum));
|
|
rcu_read_unlock();
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_ct_invert_tuplepr);
|
|
|
|
/* 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 *ct,
|
|
const struct nf_conntrack_tuple *newreply)
|
|
{
|
|
struct nf_conn_help *help = nfct_help(ct);
|
|
struct nf_conntrack_helper *helper;
|
|
|
|
/* Should be unconfirmed, so not in hash table yet */
|
|
NF_CT_ASSERT(!nf_ct_is_confirmed(ct));
|
|
|
|
pr_debug("Altering reply tuple of %p to ", ct);
|
|
NF_CT_DUMP_TUPLE(newreply);
|
|
|
|
ct->tuplehash[IP_CT_DIR_REPLY].tuple = *newreply;
|
|
if (ct->master || (help && help->expecting != 0))
|
|
return;
|
|
|
|
rcu_read_lock();
|
|
helper = __nf_ct_helper_find(newreply);
|
|
if (helper == NULL) {
|
|
if (help)
|
|
rcu_assign_pointer(help->helper, NULL);
|
|
goto out;
|
|
}
|
|
|
|
if (help == NULL) {
|
|
help = nf_ct_helper_ext_add(ct, GFP_ATOMIC);
|
|
if (help == NULL)
|
|
goto out;
|
|
} else {
|
|
memset(&help->help, 0, sizeof(help->help));
|
|
}
|
|
|
|
rcu_assign_pointer(help->helper, helper);
|
|
out:
|
|
rcu_read_unlock();
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_conntrack_alter_reply);
|
|
|
|
/* 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,
|
|
const struct sk_buff *skb,
|
|
unsigned long extra_jiffies,
|
|
int do_acct)
|
|
{
|
|
int event = 0;
|
|
|
|
NF_CT_ASSERT(ct->timeout.data == (unsigned long)ct);
|
|
NF_CT_ASSERT(skb);
|
|
|
|
write_lock_bh(&nf_conntrack_lock);
|
|
|
|
/* Only update if this is not a fixed timeout */
|
|
if (test_bit(IPS_FIXED_TIMEOUT_BIT, &ct->status))
|
|
goto acct;
|
|
|
|
/* If not in hash table, timer will not be active yet */
|
|
if (!nf_ct_is_confirmed(ct)) {
|
|
ct->timeout.expires = extra_jiffies;
|
|
event = IPCT_REFRESH;
|
|
} else {
|
|
unsigned long newtime = jiffies + extra_jiffies;
|
|
|
|
/* Only update the timeout if the new timeout is at least
|
|
HZ jiffies from the old timeout. Need del_timer for race
|
|
avoidance (may already be dying). */
|
|
if (newtime - ct->timeout.expires >= HZ
|
|
&& del_timer(&ct->timeout)) {
|
|
ct->timeout.expires = newtime;
|
|
add_timer(&ct->timeout);
|
|
event = IPCT_REFRESH;
|
|
}
|
|
}
|
|
|
|
acct:
|
|
#ifdef CONFIG_NF_CT_ACCT
|
|
if (do_acct) {
|
|
ct->counters[CTINFO2DIR(ctinfo)].packets++;
|
|
ct->counters[CTINFO2DIR(ctinfo)].bytes +=
|
|
skb->len - skb_network_offset(skb);
|
|
|
|
if ((ct->counters[CTINFO2DIR(ctinfo)].packets & 0x80000000)
|
|
|| (ct->counters[CTINFO2DIR(ctinfo)].bytes & 0x80000000))
|
|
event |= IPCT_COUNTER_FILLING;
|
|
}
|
|
#endif
|
|
|
|
write_unlock_bh(&nf_conntrack_lock);
|
|
|
|
/* must be unlocked when calling event cache */
|
|
if (event)
|
|
nf_conntrack_event_cache(event, skb);
|
|
}
|
|
EXPORT_SYMBOL_GPL(__nf_ct_refresh_acct);
|
|
|
|
#if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
|
|
|
|
#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
|
|
* or depend on ctnetlink */
|
|
int nf_ct_port_tuple_to_nlattr(struct sk_buff *skb,
|
|
const struct nf_conntrack_tuple *tuple)
|
|
{
|
|
NLA_PUT_BE16(skb, CTA_PROTO_SRC_PORT, tuple->src.u.tcp.port);
|
|
NLA_PUT_BE16(skb, CTA_PROTO_DST_PORT, tuple->dst.u.tcp.port);
|
|
return 0;
|
|
|
|
nla_put_failure:
|
|
return -1;
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_ct_port_tuple_to_nlattr);
|
|
|
|
const struct nla_policy nf_ct_port_nla_policy[CTA_PROTO_MAX+1] = {
|
|
[CTA_PROTO_SRC_PORT] = { .type = NLA_U16 },
|
|
[CTA_PROTO_DST_PORT] = { .type = NLA_U16 },
|
|
};
|
|
EXPORT_SYMBOL_GPL(nf_ct_port_nla_policy);
|
|
|
|
int nf_ct_port_nlattr_to_tuple(struct nlattr *tb[],
|
|
struct nf_conntrack_tuple *t)
|
|
{
|
|
if (!tb[CTA_PROTO_SRC_PORT] || !tb[CTA_PROTO_DST_PORT])
|
|
return -EINVAL;
|
|
|
|
t->src.u.tcp.port = nla_get_be16(tb[CTA_PROTO_SRC_PORT]);
|
|
t->dst.u.tcp.port = nla_get_be16(tb[CTA_PROTO_DST_PORT]);
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_ct_port_nlattr_to_tuple);
|
|
#endif
|
|
|
|
/* Used by ipt_REJECT and ip6t_REJECT. */
|
|
static void nf_conntrack_attach(struct sk_buff *nskb, struct sk_buff *skb)
|
|
{
|
|
struct nf_conn *ct;
|
|
enum ip_conntrack_info ctinfo;
|
|
|
|
/* This ICMP is in reverse direction to the packet which caused it */
|
|
ct = nf_ct_get(skb, &ctinfo);
|
|
if (CTINFO2DIR(ctinfo) == IP_CT_DIR_ORIGINAL)
|
|
ctinfo = IP_CT_RELATED + IP_CT_IS_REPLY;
|
|
else
|
|
ctinfo = IP_CT_RELATED;
|
|
|
|
/* Attach to new skbuff, and increment count */
|
|
nskb->nfct = &ct->ct_general;
|
|
nskb->nfctinfo = ctinfo;
|
|
nf_conntrack_get(nskb->nfct);
|
|
}
|
|
|
|
static inline int
|
|
do_iter(const struct nf_conntrack_tuple_hash *i,
|
|
int (*iter)(struct nf_conn *i, void *data),
|
|
void *data)
|
|
{
|
|
return iter(nf_ct_tuplehash_to_ctrack(i), data);
|
|
}
|
|
|
|
/* Bring out ya dead! */
|
|
static struct nf_conn *
|
|
get_next_corpse(int (*iter)(struct nf_conn *i, void *data),
|
|
void *data, unsigned int *bucket)
|
|
{
|
|
struct nf_conntrack_tuple_hash *h;
|
|
struct nf_conn *ct;
|
|
struct hlist_node *n;
|
|
|
|
write_lock_bh(&nf_conntrack_lock);
|
|
for (; *bucket < nf_conntrack_htable_size; (*bucket)++) {
|
|
hlist_for_each_entry(h, n, &nf_conntrack_hash[*bucket], hnode) {
|
|
ct = nf_ct_tuplehash_to_ctrack(h);
|
|
if (iter(ct, data))
|
|
goto found;
|
|
}
|
|
}
|
|
hlist_for_each_entry(h, n, &unconfirmed, hnode) {
|
|
ct = nf_ct_tuplehash_to_ctrack(h);
|
|
if (iter(ct, data))
|
|
set_bit(IPS_DYING_BIT, &ct->status);
|
|
}
|
|
write_unlock_bh(&nf_conntrack_lock);
|
|
return NULL;
|
|
found:
|
|
atomic_inc(&ct->ct_general.use);
|
|
write_unlock_bh(&nf_conntrack_lock);
|
|
return ct;
|
|
}
|
|
|
|
void
|
|
nf_ct_iterate_cleanup(int (*iter)(struct nf_conn *i, void *data), void *data)
|
|
{
|
|
struct nf_conn *ct;
|
|
unsigned int bucket = 0;
|
|
|
|
while ((ct = get_next_corpse(iter, data, &bucket)) != NULL) {
|
|
/* Time to push up daises... */
|
|
if (del_timer(&ct->timeout))
|
|
death_by_timeout((unsigned long)ct);
|
|
/* ... else the timer will get him soon. */
|
|
|
|
nf_ct_put(ct);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_ct_iterate_cleanup);
|
|
|
|
static int kill_all(struct nf_conn *i, void *data)
|
|
{
|
|
return 1;
|
|
}
|
|
|
|
void nf_ct_free_hashtable(struct hlist_head *hash, int vmalloced, unsigned int size)
|
|
{
|
|
if (vmalloced)
|
|
vfree(hash);
|
|
else
|
|
free_pages((unsigned long)hash,
|
|
get_order(sizeof(struct hlist_head) * size));
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_ct_free_hashtable);
|
|
|
|
void nf_conntrack_flush(void)
|
|
{
|
|
nf_ct_iterate_cleanup(kill_all, NULL);
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_conntrack_flush);
|
|
|
|
/* Mishearing the voices in his head, our hero wonders how he's
|
|
supposed to kill the mall. */
|
|
void nf_conntrack_cleanup(void)
|
|
{
|
|
rcu_assign_pointer(ip_ct_attach, NULL);
|
|
|
|
/* This makes sure all current packets have passed through
|
|
netfilter framework. Roll on, two-stage module
|
|
delete... */
|
|
synchronize_net();
|
|
|
|
nf_ct_event_cache_flush();
|
|
i_see_dead_people:
|
|
nf_conntrack_flush();
|
|
if (atomic_read(&nf_conntrack_count) != 0) {
|
|
schedule();
|
|
goto i_see_dead_people;
|
|
}
|
|
/* wait until all references to nf_conntrack_untracked are dropped */
|
|
while (atomic_read(&nf_conntrack_untracked.ct_general.use) > 1)
|
|
schedule();
|
|
|
|
rcu_assign_pointer(nf_ct_destroy, NULL);
|
|
|
|
kmem_cache_destroy(nf_conntrack_cachep);
|
|
nf_ct_free_hashtable(nf_conntrack_hash, nf_conntrack_vmalloc,
|
|
nf_conntrack_htable_size);
|
|
|
|
nf_conntrack_proto_fini();
|
|
nf_conntrack_helper_fini();
|
|
nf_conntrack_expect_fini();
|
|
}
|
|
|
|
struct hlist_head *nf_ct_alloc_hashtable(unsigned int *sizep, int *vmalloced)
|
|
{
|
|
struct hlist_head *hash;
|
|
unsigned int size, i;
|
|
|
|
*vmalloced = 0;
|
|
|
|
size = *sizep = roundup(*sizep, PAGE_SIZE / sizeof(struct hlist_head));
|
|
hash = (void*)__get_free_pages(GFP_KERNEL|__GFP_NOWARN,
|
|
get_order(sizeof(struct hlist_head)
|
|
* size));
|
|
if (!hash) {
|
|
*vmalloced = 1;
|
|
printk(KERN_WARNING "nf_conntrack: falling back to vmalloc.\n");
|
|
hash = vmalloc(sizeof(struct hlist_head) * size);
|
|
}
|
|
|
|
if (hash)
|
|
for (i = 0; i < size; i++)
|
|
INIT_HLIST_HEAD(&hash[i]);
|
|
|
|
return hash;
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_ct_alloc_hashtable);
|
|
|
|
int nf_conntrack_set_hashsize(const char *val, struct kernel_param *kp)
|
|
{
|
|
int i, bucket, vmalloced, old_vmalloced;
|
|
unsigned int hashsize, old_size;
|
|
int rnd;
|
|
struct hlist_head *hash, *old_hash;
|
|
struct nf_conntrack_tuple_hash *h;
|
|
|
|
/* On boot, we can set this without any fancy locking. */
|
|
if (!nf_conntrack_htable_size)
|
|
return param_set_uint(val, kp);
|
|
|
|
hashsize = simple_strtoul(val, NULL, 0);
|
|
if (!hashsize)
|
|
return -EINVAL;
|
|
|
|
hash = nf_ct_alloc_hashtable(&hashsize, &vmalloced);
|
|
if (!hash)
|
|
return -ENOMEM;
|
|
|
|
/* We have to rehahs for the new table anyway, so we also can
|
|
* use a newrandom seed */
|
|
get_random_bytes(&rnd, 4);
|
|
|
|
/* Lookups in the old hash might happen in parallel, which means we
|
|
* might get false negatives during connection lookup. New connections
|
|
* created because of a false negative won't make it into the hash
|
|
* though since that required taking the lock.
|
|
*/
|
|
write_lock_bh(&nf_conntrack_lock);
|
|
for (i = 0; i < nf_conntrack_htable_size; i++) {
|
|
while (!hlist_empty(&nf_conntrack_hash[i])) {
|
|
h = hlist_entry(nf_conntrack_hash[i].first,
|
|
struct nf_conntrack_tuple_hash, hnode);
|
|
hlist_del_rcu(&h->hnode);
|
|
bucket = __hash_conntrack(&h->tuple, hashsize, rnd);
|
|
hlist_add_head(&h->hnode, &hash[bucket]);
|
|
}
|
|
}
|
|
old_size = nf_conntrack_htable_size;
|
|
old_vmalloced = nf_conntrack_vmalloc;
|
|
old_hash = nf_conntrack_hash;
|
|
|
|
nf_conntrack_htable_size = hashsize;
|
|
nf_conntrack_vmalloc = vmalloced;
|
|
nf_conntrack_hash = hash;
|
|
nf_conntrack_hash_rnd = rnd;
|
|
write_unlock_bh(&nf_conntrack_lock);
|
|
|
|
nf_ct_free_hashtable(old_hash, old_vmalloced, old_size);
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_conntrack_set_hashsize);
|
|
|
|
module_param_call(hashsize, nf_conntrack_set_hashsize, param_get_uint,
|
|
&nf_conntrack_htable_size, 0600);
|
|
|
|
int __init nf_conntrack_init(void)
|
|
{
|
|
int max_factor = 8;
|
|
int ret;
|
|
|
|
/* Idea from tcp.c: use 1/16384 of memory. On i386: 32MB
|
|
* machine has 512 buckets. >= 1GB machines have 16384 buckets. */
|
|
if (!nf_conntrack_htable_size) {
|
|
nf_conntrack_htable_size
|
|
= (((num_physpages << PAGE_SHIFT) / 16384)
|
|
/ sizeof(struct hlist_head));
|
|
if (num_physpages > (1024 * 1024 * 1024 / PAGE_SIZE))
|
|
nf_conntrack_htable_size = 16384;
|
|
if (nf_conntrack_htable_size < 32)
|
|
nf_conntrack_htable_size = 32;
|
|
|
|
/* Use a max. factor of four by default to get the same max as
|
|
* with the old struct list_heads. When a table size is given
|
|
* we use the old value of 8 to avoid reducing the max.
|
|
* entries. */
|
|
max_factor = 4;
|
|
}
|
|
nf_conntrack_hash = nf_ct_alloc_hashtable(&nf_conntrack_htable_size,
|
|
&nf_conntrack_vmalloc);
|
|
if (!nf_conntrack_hash) {
|
|
printk(KERN_ERR "Unable to create nf_conntrack_hash\n");
|
|
goto err_out;
|
|
}
|
|
|
|
nf_conntrack_max = max_factor * nf_conntrack_htable_size;
|
|
|
|
printk("nf_conntrack version %s (%u buckets, %d max)\n",
|
|
NF_CONNTRACK_VERSION, nf_conntrack_htable_size,
|
|
nf_conntrack_max);
|
|
|
|
nf_conntrack_cachep = kmem_cache_create("nf_conntrack",
|
|
sizeof(struct nf_conn),
|
|
0, 0, NULL);
|
|
if (!nf_conntrack_cachep) {
|
|
printk(KERN_ERR "Unable to create nf_conn slab cache\n");
|
|
goto err_free_hash;
|
|
}
|
|
|
|
ret = nf_conntrack_proto_init();
|
|
if (ret < 0)
|
|
goto err_free_conntrack_slab;
|
|
|
|
ret = nf_conntrack_expect_init();
|
|
if (ret < 0)
|
|
goto out_fini_proto;
|
|
|
|
ret = nf_conntrack_helper_init();
|
|
if (ret < 0)
|
|
goto out_fini_expect;
|
|
|
|
/* For use by REJECT target */
|
|
rcu_assign_pointer(ip_ct_attach, nf_conntrack_attach);
|
|
rcu_assign_pointer(nf_ct_destroy, destroy_conntrack);
|
|
|
|
/* Set up fake conntrack:
|
|
- to never be deleted, not in any hashes */
|
|
atomic_set(&nf_conntrack_untracked.ct_general.use, 1);
|
|
/* - and look it like as a confirmed connection */
|
|
set_bit(IPS_CONFIRMED_BIT, &nf_conntrack_untracked.status);
|
|
|
|
return ret;
|
|
|
|
out_fini_expect:
|
|
nf_conntrack_expect_fini();
|
|
out_fini_proto:
|
|
nf_conntrack_proto_fini();
|
|
err_free_conntrack_slab:
|
|
kmem_cache_destroy(nf_conntrack_cachep);
|
|
err_free_hash:
|
|
nf_ct_free_hashtable(nf_conntrack_hash, nf_conntrack_vmalloc,
|
|
nf_conntrack_htable_size);
|
|
err_out:
|
|
return -ENOMEM;
|
|
}
|