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[NETFILTER]: nf_conntrack: use extension infrastructure for helper

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Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Yasuyuki Kozakai 2007-07-07 22:23:42 -07:00 committed by David S. Miller
parent ecfab2c9fe
commit ceceae1b15
8 changed files with 99 additions and 92 deletions
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26
include/net/netfilter/nf_conntrack.h
View File

@ -294,32 +294,6 @@ static inline struct nf_conn_nat *nfct_nat(const struct nf_conn *ct)
offset = ALIGN(offset, __alignof__(struct nf_conn_nat));
return (struct nf_conn_nat *) ((void *)ct + offset);
}
static inline struct nf_conn_help *nfct_help(const struct nf_conn *ct)
{
unsigned int offset = sizeof(struct nf_conn);
if (!(ct->features & NF_CT_F_HELP))
return NULL;
if (ct->features & NF_CT_F_NAT) {
offset = ALIGN(offset, __alignof__(struct nf_conn_nat));
offset += sizeof(struct nf_conn_nat);
}
offset = ALIGN(offset, __alignof__(struct nf_conn_help));
return (struct nf_conn_help *) ((void *)ct + offset);
}
#else /* No NAT */
static inline struct nf_conn_help *nfct_help(const struct nf_conn *ct)
{
unsigned int offset = sizeof(struct nf_conn);
if (!(ct->features & NF_CT_F_HELP))
return NULL;
offset = ALIGN(offset, __alignof__(struct nf_conn_help));
return (struct nf_conn_help *) ((void *)ct + offset);
}
#endif /* CONFIG_NF_NAT_NEEDED */
#endif /* __KERNEL__ */
#endif /* _NF_CONNTRACK_H */

3
include/net/netfilter/nf_conntrack_core.h
View File

@ -30,6 +30,9 @@ extern void nf_conntrack_cleanup(void);
extern int nf_conntrack_proto_init(void);
extern void nf_conntrack_proto_fini(void);
extern int nf_conntrack_helper_init(void);
extern void nf_conntrack_helper_fini(void);
struct nf_conntrack_l3proto;
extern struct nf_conntrack_l3proto *nf_ct_find_l3proto(u_int16_t pf);
/* Like above, but you already have conntrack read lock. */

3
include/net/netfilter/nf_conntrack_extend.h
View File

@ -5,9 +5,12 @@
enum nf_ct_ext_id
{
NF_CT_EXT_HELPER,
NF_CT_EXT_NUM,
};
#define NF_CT_EXT_HELPER_TYPE struct nf_conn_help
/* Extensions: optional stuff which isn't permanently in struct. */
struct nf_ct_ext {
u8 offset[NF_CT_EXT_NUM];

5
include/net/netfilter/nf_conntrack_helper.h
View File

@ -10,6 +10,7 @@
#ifndef _NF_CONNTRACK_HELPER_H
#define _NF_CONNTRACK_HELPER_H
#include <net/netfilter/nf_conntrack.h>
#include <net/netfilter/nf_conntrack_extend.h>
struct module;
@ -52,4 +53,8 @@ extern void nf_ct_helper_put(struct nf_conntrack_helper *helper);
extern int nf_conntrack_helper_register(struct nf_conntrack_helper *);
extern void nf_conntrack_helper_unregister(struct nf_conntrack_helper *);
static inline struct nf_conn_help *nfct_help(const struct nf_conn *ct)
{
return nf_ct_ext_find(ct, NF_CT_EXT_HELPER);
}
#endif /*_NF_CONNTRACK_HELPER_H*/

10
net/ipv4/netfilter/nf_nat_standalone.c
View File

@ -338,14 +338,6 @@ static int __init nf_nat_standalone_init(void)
return ret;
}
size = ALIGN(size, __alignof__(struct nf_conn_help)) +
sizeof(struct nf_conn_help);
ret = nf_conntrack_register_cache(NF_CT_F_NAT|NF_CT_F_HELP,
"nf_nat:help", size);
if (ret < 0) {
printk(KERN_ERR "nf_nat_init: Unable to create slab cache\n");
goto cleanup_register_cache;
}
#ifdef CONFIG_XFRM
BUG_ON(ip_nat_decode_session != NULL);
ip_nat_decode_session = nat_decode_session;
@ -370,8 +362,6 @@ static int __init nf_nat_standalone_init(void)
ip_nat_decode_session = NULL;
synchronize_net();
#endif
nf_conntrack_unregister_cache(NF_CT_F_NAT|NF_CT_F_HELP);
cleanup_register_cache:
nf_conntrack_unregister_cache(NF_CT_F_NAT);
return ret;
}

76
net/netfilter/nf_conntrack_core.c
View File

@ -566,7 +566,6 @@ __nf_conntrack_alloc(const struct nf_conntrack_tuple *orig,
u_int32_t features)
{
struct nf_conn *conntrack = NULL;
struct nf_conntrack_helper *helper;
if (unlikely(!nf_conntrack_hash_rnd_initted)) {
get_random_bytes(&nf_conntrack_hash_rnd, 4);
@ -593,14 +592,6 @@ __nf_conntrack_alloc(const struct nf_conntrack_tuple *orig,
/* find features needed by this conntrack. */
features |= l3proto->get_features(orig);
/* FIXME: protect helper list per RCU */
read_lock_bh(&nf_conntrack_lock);
helper = __nf_ct_helper_find(repl);
/* NAT might want to assign a helper later */
if (helper || features & NF_CT_F_NAT)
features |= NF_CT_F_HELP;
read_unlock_bh(&nf_conntrack_lock);
DEBUGP("nf_conntrack_alloc: features=0x%x\n", features);
read_lock_bh(&nf_ct_cache_lock);
@ -681,12 +672,6 @@ init_conntrack(const struct nf_conntrack_tuple *tuple,
return NULL;
}
read_lock_bh(&nf_conntrack_lock);
exp = __nf_conntrack_expect_find(tuple);
if (exp && exp->helper)
features = NF_CT_F_HELP;
read_unlock_bh(&nf_conntrack_lock);
conntrack = __nf_conntrack_alloc(tuple, &repl_tuple, l3proto, features);
if (conntrack == NULL || IS_ERR(conntrack)) {
DEBUGP("Can't allocate conntrack.\n");
@ -701,16 +686,21 @@ init_conntrack(const struct nf_conntrack_tuple *tuple,
write_lock_bh(&nf_conntrack_lock);
exp = find_expectation(tuple);
help = nfct_help(conntrack);
if (exp) {
DEBUGP("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)
if (exp->helper) {
help = nf_ct_ext_add(conntrack, NF_CT_EXT_HELPER,
GFP_ATOMIC);
if (help)
rcu_assign_pointer(help->helper, exp->helper);
else
DEBUGP("failed to add helper extension area");
}
#ifdef CONFIG_NF_CONNTRACK_MARK
conntrack->mark = exp->master->mark;
#endif
@ -720,10 +710,18 @@ init_conntrack(const struct nf_conntrack_tuple *tuple,
nf_conntrack_get(&conntrack->master->ct_general);
NF_CT_STAT_INC(expect_new);
} else {
if (help) {
/* not in hash table yet, so not strictly necessary */
rcu_assign_pointer(help->helper,
__nf_ct_helper_find(&repl_tuple));
struct nf_conntrack_helper *helper;
helper = __nf_ct_helper_find(&repl_tuple);
if (helper) {
help = nf_ct_ext_add(conntrack, NF_CT_EXT_HELPER,
GFP_ATOMIC);
if (help)
/* not in hash table yet, so not strictly
necessary */
rcu_assign_pointer(help->helper, helper);
else
DEBUGP("failed to add helper extension area");
}
NF_CT_STAT_INC(new);
}
@ -892,6 +890,7 @@ 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;
write_lock_bh(&nf_conntrack_lock);
/* Should be unconfirmed, so not in hash table yet */
@ -901,14 +900,28 @@ void nf_conntrack_alter_reply(struct nf_conn *ct,
NF_CT_DUMP_TUPLE(newreply);
ct->tuplehash[IP_CT_DIR_REPLY].tuple = *newreply;
if (!ct->master && help && help->expecting == 0) {
struct nf_conntrack_helper *helper;
if (ct->master || (help && help->expecting != 0))
goto out;
helper = __nf_ct_helper_find(newreply);
if (helper)
memset(&help->help, 0, sizeof(help->help));
/* not in hash table yet, so not strictly necessary */
rcu_assign_pointer(help->helper, helper);
if (helper == NULL) {
if (help)
rcu_assign_pointer(help->helper, NULL);
goto out;
}
if (help == NULL) {
help = nf_ct_ext_add(ct, NF_CT_EXT_HELPER, GFP_ATOMIC);
if (help == NULL) {
DEBUGP("failed to add helper extension area");
goto out;
}
} else {
memset(&help->help, 0, sizeof(help->help));
}
rcu_assign_pointer(help->helper, helper);
out:
write_unlock_bh(&nf_conntrack_lock);
}
EXPORT_SYMBOL_GPL(nf_conntrack_alter_reply);
@ -1150,6 +1163,7 @@ void nf_conntrack_cleanup(void)
nf_conntrack_htable_size);
nf_conntrack_proto_fini();
nf_conntrack_helper_fini();
}
static struct list_head *alloc_hashtable(int size, int *vmalloced)
@ -1272,6 +1286,10 @@ int __init nf_conntrack_init(void)
if (ret < 0)
goto out_free_expect_slab;
ret = nf_conntrack_helper_init();
if (ret < 0)
goto out_fini_proto;
/* For use by REJECT target */
rcu_assign_pointer(ip_ct_attach, __nf_conntrack_attach);
rcu_assign_pointer(nf_ct_destroy, destroy_conntrack);
@ -1284,6 +1302,8 @@ int __init nf_conntrack_init(void)
return ret;
out_fini_proto:
nf_conntrack_proto_fini();
out_free_expect_slab:
kmem_cache_destroy(nf_conntrack_expect_cachep);
err_free_conntrack_slab:

27
net/netfilter/nf_conntrack_helper.c
View File

@ -26,6 +26,7 @@
#include <net/netfilter/nf_conntrack_l4proto.h>
#include <net/netfilter/nf_conntrack_helper.h>
#include <net/netfilter/nf_conntrack_core.h>
#include <net/netfilter/nf_conntrack_extend.h>
static __read_mostly LIST_HEAD(helpers);
@ -100,18 +101,8 @@ static inline int unhelp(struct nf_conntrack_tuple_hash *i,
int nf_conntrack_helper_register(struct nf_conntrack_helper *me)
{
int size, ret;
BUG_ON(me->timeout == 0);
size = ALIGN(sizeof(struct nf_conn), __alignof__(struct nf_conn_help)) +
sizeof(struct nf_conn_help);
ret = nf_conntrack_register_cache(NF_CT_F_HELP, "nf_conntrack:help",
size);
if (ret < 0) {
printk(KERN_ERR "nf_conntrack_helper_register: 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);
@ -153,3 +144,19 @@ void nf_conntrack_helper_unregister(struct nf_conntrack_helper *me)
synchronize_net();
}
EXPORT_SYMBOL_GPL(nf_conntrack_helper_unregister);
struct nf_ct_ext_type helper_extend = {
.len = sizeof(struct nf_conn_help),
.align = __alignof__(struct nf_conn_help),
.id = NF_CT_EXT_HELPER,
};
int nf_conntrack_helper_init()
{
return nf_ct_extend_register(&helper_extend);
}
void nf_conntrack_helper_fini()
{
nf_ct_extend_unregister(&helper_extend);
}

25
net/netfilter/nf_conntrack_netlink.c
View File

@ -856,23 +856,23 @@ ctnetlink_change_helper(struct nf_conn *ct, struct nfattr *cda[])
return 0;
}
if (!help) {
/* FIXME: we need to reallocate and rehash */
return -EBUSY;
}
helper = __nf_conntrack_helper_find_byname(helpname);
if (helper == NULL)
return -EINVAL;
if (help) {
if (help->helper == helper)
return 0;
if (help->helper)
return -EBUSY;
/* need to zero data of old helper */
memset(&help->help, 0, sizeof(help->help));
} else {
help = nf_ct_ext_add(ct, NF_CT_EXT_HELPER, GFP_KERNEL);
if (help == NULL)
return -ENOMEM;
}
rcu_assign_pointer(help->helper, helper);
return 0;
@ -957,7 +957,7 @@ ctnetlink_create_conntrack(struct nfattr *cda[],
struct nf_conn *ct;
int err = -EINVAL;
struct nf_conn_help *help;
struct nf_conntrack_helper *helper = NULL;
struct nf_conntrack_helper *helper;
ct = nf_conntrack_alloc(otuple, rtuple);
if (ct == NULL || IS_ERR(ct))
@ -987,9 +987,14 @@ ctnetlink_create_conntrack(struct nfattr *cda[],
ct->mark = ntohl(*(__be32 *)NFA_DATA(cda[CTA_MARK-1]));
#endif
help = nfct_help(ct);
if (help) {
helper = nf_ct_helper_find_get(rtuple);
if (helper) {
help = nf_ct_ext_add(ct, NF_CT_EXT_HELPER, GFP_KERNEL);
if (help == NULL) {
nf_ct_helper_put(helper);
err = -ENOMEM;
goto err;
}
/* not in hash table yet so not strictly necessary */
rcu_assign_pointer(help->helper, helper);
}