mirror of
https://github.com/torvalds/linux
synced 2024-11-05 18:23:50 +00:00
[NETFILTER]: nf_conntrack: split out expectation handling
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>
This commit is contained in:
parent
d2e4bdc870
commit
77ab9cff0f
10 changed files with 452 additions and 401 deletions
|
@ -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;
|
||||
|
|
|
@ -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 ;
|
||||
|
|
72
include/net/netfilter/nf_conntrack_expect.h
Normal file
72
include/net/netfilter/nf_conntrack_expect.h
Normal file
|
@ -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*/
|
||||
|
|
@ -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*/
|
||||
|
|
|
@ -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
|
||||
|
||||
|
|
|
@ -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;
|
||||
|
|
365
net/netfilter/nf_conntrack_expect.c
Normal file
365
net/netfilter/nf_conntrack_expect.c
Normal file
|
@ -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 */
|
|
@ -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>
|
||||
|
||||
|
|
|
@ -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>
|
||||
|
|
|
@ -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;
|
||||
|
|
Loading…
Reference in a new issue