netfilter: Export nf_ct_{set,destroy}_timeout()

This patch exports nf_ct_set_timeout() and nf_ct_destroy_timeout().
The two functions are derived from xt_ct_destroy_timeout() and
xt_ct_set_timeout() in xt_CT.c, and moved to nf_conntrack_timeout.c
without any functional change.
It would be useful for other users (i.e. OVS) that utilizes the
finer-grain conntrack timeout feature.

CC: Pablo Neira Ayuso <pablo@netfilter.org>
CC: Pravin Shelar <pshelar@ovn.org>
Signed-off-by: Yi-Hung Wei <yihung.wei@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Yi-Hung Wei 2019-03-26 11:31:13 -07:00 committed by David S. Miller
parent c63d11ba52
commit 717700d183
3 changed files with 110 additions and 87 deletions

View File

@ -88,6 +88,9 @@ static inline unsigned int *nf_ct_timeout_lookup(const struct nf_conn *ct)
int nf_conntrack_timeout_init(void);
void nf_conntrack_timeout_fini(void);
void nf_ct_untimeout(struct net *net, struct nf_ct_timeout *timeout);
int nf_ct_set_timeout(struct net *net, struct nf_conn *ct, u8 l3num, u8 l4num,
const char *timeout_name);
void nf_ct_destroy_timeout(struct nf_conn *ct);
#else
static inline int nf_conntrack_timeout_init(void)
{
@ -98,6 +101,18 @@ static inline void nf_conntrack_timeout_fini(void)
{
return;
}
static inline int nf_ct_set_timeout(struct net *net, struct nf_conn *ct,
u8 l3num, u8 l4num,
const char *timeout_name)
{
return -EOPNOTSUPP;
}
static inline void nf_ct_destroy_timeout(struct nf_conn *ct)
{
return;
}
#endif /* CONFIG_NF_CONNTRACK_TIMEOUT */
#ifdef CONFIG_NF_CONNTRACK_TIMEOUT

View File

@ -48,6 +48,95 @@ void nf_ct_untimeout(struct net *net, struct nf_ct_timeout *timeout)
}
EXPORT_SYMBOL_GPL(nf_ct_untimeout);
static void __nf_ct_timeout_put(struct nf_ct_timeout *timeout)
{
typeof(nf_ct_timeout_put_hook) timeout_put;
timeout_put = rcu_dereference(nf_ct_timeout_put_hook);
if (timeout_put)
timeout_put(timeout);
}
int nf_ct_set_timeout(struct net *net, struct nf_conn *ct,
u8 l3num, u8 l4num, const char *timeout_name)
{
typeof(nf_ct_timeout_find_get_hook) timeout_find_get;
struct nf_ct_timeout *timeout;
struct nf_conn_timeout *timeout_ext;
const char *errmsg = NULL;
int ret = 0;
rcu_read_lock();
timeout_find_get = rcu_dereference(nf_ct_timeout_find_get_hook);
if (!timeout_find_get) {
ret = -ENOENT;
errmsg = "Timeout policy base is empty";
goto out;
}
timeout = timeout_find_get(net, timeout_name);
if (!timeout) {
ret = -ENOENT;
pr_info_ratelimited("No such timeout policy \"%s\"\n",
timeout_name);
goto out;
}
if (timeout->l3num != l3num) {
ret = -EINVAL;
pr_info_ratelimited("Timeout policy `%s' can only be used by "
"L%d protocol number %d\n",
timeout_name, 3, timeout->l3num);
goto err_put_timeout;
}
/* Make sure the timeout policy matches any existing protocol tracker,
* otherwise default to generic.
*/
if (timeout->l4proto->l4proto != l4num) {
ret = -EINVAL;
pr_info_ratelimited("Timeout policy `%s' can only be used by "
"L%d protocol number %d\n",
timeout_name, 4, timeout->l4proto->l4proto);
goto err_put_timeout;
}
timeout_ext = nf_ct_timeout_ext_add(ct, timeout, GFP_ATOMIC);
if (!timeout_ext) {
ret = -ENOMEM;
goto err_put_timeout;
}
rcu_read_unlock();
return ret;
err_put_timeout:
__nf_ct_timeout_put(timeout);
out:
rcu_read_unlock();
if (errmsg)
pr_info_ratelimited("%s\n", errmsg);
return ret;
}
EXPORT_SYMBOL_GPL(nf_ct_set_timeout);
void nf_ct_destroy_timeout(struct nf_conn *ct)
{
struct nf_conn_timeout *timeout_ext;
typeof(nf_ct_timeout_put_hook) timeout_put;
rcu_read_lock();
timeout_put = rcu_dereference(nf_ct_timeout_put_hook);
if (timeout_put) {
timeout_ext = nf_ct_timeout_find(ct);
if (timeout_ext) {
timeout_put(timeout_ext->timeout);
RCU_INIT_POINTER(timeout_ext->timeout, NULL);
}
}
rcu_read_unlock();
}
EXPORT_SYMBOL_GPL(nf_ct_destroy_timeout);
static const struct nf_ct_ext_type timeout_extend = {
.len = sizeof(struct nf_conn_timeout),
.align = __alignof__(struct nf_conn_timeout),

View File

@ -103,85 +103,24 @@ xt_ct_set_helper(struct nf_conn *ct, const char *helper_name,
return 0;
}
#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
static void __xt_ct_tg_timeout_put(struct nf_ct_timeout *timeout)
{
typeof(nf_ct_timeout_put_hook) timeout_put;
timeout_put = rcu_dereference(nf_ct_timeout_put_hook);
if (timeout_put)
timeout_put(timeout);
}
#endif
static int
xt_ct_set_timeout(struct nf_conn *ct, const struct xt_tgchk_param *par,
const char *timeout_name)
{
#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
typeof(nf_ct_timeout_find_get_hook) timeout_find_get;
const struct nf_conntrack_l4proto *l4proto;
struct nf_ct_timeout *timeout;
struct nf_conn_timeout *timeout_ext;
const char *errmsg = NULL;
int ret = 0;
u8 proto;
rcu_read_lock();
timeout_find_get = rcu_dereference(nf_ct_timeout_find_get_hook);
if (timeout_find_get == NULL) {
ret = -ENOENT;
errmsg = "Timeout policy base is empty";
goto out;
}
proto = xt_ct_find_proto(par);
if (!proto) {
ret = -EINVAL;
errmsg = "You must specify a L4 protocol and not use inversions on it";
goto out;
pr_info_ratelimited("You must specify a L4 protocol and not "
"use inversions on it");
return -EINVAL;
}
timeout = timeout_find_get(par->net, timeout_name);
if (timeout == NULL) {
ret = -ENOENT;
pr_info_ratelimited("No such timeout policy \"%s\"\n",
timeout_name);
goto out;
}
if (timeout->l3num != par->family) {
ret = -EINVAL;
pr_info_ratelimited("Timeout policy `%s' can only be used by L%d protocol number %d\n",
timeout_name, 3, timeout->l3num);
goto err_put_timeout;
}
/* Make sure the timeout policy matches any existing protocol tracker,
* otherwise default to generic.
*/
l4proto = nf_ct_l4proto_find(proto);
if (timeout->l4proto->l4proto != l4proto->l4proto) {
ret = -EINVAL;
pr_info_ratelimited("Timeout policy `%s' can only be used by L%d protocol number %d\n",
timeout_name, 4, timeout->l4proto->l4proto);
goto err_put_timeout;
}
timeout_ext = nf_ct_timeout_ext_add(ct, timeout, GFP_ATOMIC);
if (!timeout_ext) {
ret = -ENOMEM;
goto err_put_timeout;
}
return nf_ct_set_timeout(par->net, ct, par->family, l4proto->l4proto,
timeout_name);
rcu_read_unlock();
return ret;
err_put_timeout:
__xt_ct_tg_timeout_put(timeout);
out:
rcu_read_unlock();
if (errmsg)
pr_info_ratelimited("%s\n", errmsg);
return ret;
#else
return -EOPNOTSUPP;
#endif
@ -328,26 +267,6 @@ static int xt_ct_tg_check_v2(const struct xt_tgchk_param *par)
return xt_ct_tg_check(par, par->targinfo);
}
static void xt_ct_destroy_timeout(struct nf_conn *ct)
{
#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
struct nf_conn_timeout *timeout_ext;
typeof(nf_ct_timeout_put_hook) timeout_put;
rcu_read_lock();
timeout_put = rcu_dereference(nf_ct_timeout_put_hook);
if (timeout_put) {
timeout_ext = nf_ct_timeout_find(ct);
if (timeout_ext) {
timeout_put(timeout_ext->timeout);
RCU_INIT_POINTER(timeout_ext->timeout, NULL);
}
}
rcu_read_unlock();
#endif
}
static void xt_ct_tg_destroy(const struct xt_tgdtor_param *par,
struct xt_ct_target_info_v1 *info)
{
@ -361,7 +280,7 @@ static void xt_ct_tg_destroy(const struct xt_tgdtor_param *par,
nf_ct_netns_put(par->net, par->family);
xt_ct_destroy_timeout(ct);
nf_ct_destroy_timeout(ct);
nf_ct_put(info->ct);
}
}