This patch allows to add, list and delete connection tracking timeout
policies via nft objref infrastructure and assigning these timeout
via nft rule.
Ruleset:
table ip raw {
ct timeout cttime {
protocol tcp
established 111 close 13
l3proto ip
}
chain output {
type filter hook output priority -300; policy accept;
ct timeout set "cttime"
}
}
%./libnftnl/examples/nft-ct-timeout-add ip raw cttime tcp
%./libnftnl/examples/nft-rule-ct-timeout-add ip raw output cttime
%conntrack -E
[NEW] tcp 6 111 ESTABLISHED src=172.16.19.128 dst=172.16.19.1
sport=22 dport=41360 [UNREPLIED] src=172.16.19.1 dst=172.16.19.128
sport=41360 dport=22
Signed-off-by: Harsha Sharma <harshasharmaiitr@xxxxxxxxx>
---
Changes in v7:
- initialise list_head for nfct_timeout_list in nf_tables_api
- use nf_ct_untimeout for cleanup
- other minor changes
Changes in v6:
- Remove unnecessary chunks
- initialise timeout list in nf_tables_api.c
- minor changes
Changes in v5:
- wrap with NF_CT_NETLINK_TIMEOUT option
- attach timeout template in init
- other minor changes
Changes in v4:
- Remove unused attributes
- allocate template from init() path
- minor changes
- updated log message
- pull to latest tree
Changes in v3:
- Use nf_ct_tmpl_alloc to attach timeout via template conntrack.
Changes in v2:
- Add code for nft_ct_timeout_obj_eval
- remove likely() from code
- remove vla in ctnl_timeout_parse_policy
include/uapi/linux/netfilter/nf_tables.h | 14 ++-
net/netfilter/nf_tables_api.c | 4 +
net/netfilter/nft_ct.c | 192 +++++++++++++++++++++++++++++++
3 files changed, 209 insertions(+), 1 deletion(-)
diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h
index 89438e68dc03..552fa5a6b7c3 100644
--- a/include/uapi/linux/netfilter/nf_tables.h
+++ b/include/uapi/linux/netfilter/nf_tables.h
@@ -955,6 +955,7 @@ enum nft_socket_keys {
* @NFT_CT_DST_IP: conntrack layer 3 protocol destination (IPv4 address)
* @NFT_CT_SRC_IP6: conntrack layer 3 protocol source (IPv6 address)
* @NFT_CT_DST_IP6: conntrack layer 3 protocol destination (IPv6 address)
+ * @NFT_CT_TIMEOUT: connection tracking timeout policy assigned to conntrack
*/
enum nft_ct_keys {
NFT_CT_STATE,
@@ -980,6 +981,7 @@ enum nft_ct_keys {
NFT_CT_DST_IP,
NFT_CT_SRC_IP6,
NFT_CT_DST_IP6,
+ NFT_CT_TIMEOUT,
__NFT_CT_MAX
};
#define NFT_CT_MAX (__NFT_CT_MAX - 1)
@@ -1392,13 +1394,23 @@ enum nft_ct_helper_attributes {
};
#define NFTA_CT_HELPER_MAX (__NFTA_CT_HELPER_MAX - 1)
+enum nft_ct_timeout_timeout_attributes {
+ NFTA_CT_TIMEOUT_UNSPEC,
+ NFTA_CT_TIMEOUT_L3PROTO,
+ NFTA_CT_TIMEOUT_L4PROTO,
+ NFTA_CT_TIMEOUT_DATA,
+ __NFTA_CT_TIMEOUT_MAX,
+};
+#define NFTA_CT_TIMEOUT_MAX (__NFTA_CT_TIMEOUT_MAX - 1)
+
#define NFT_OBJECT_UNSPEC 0
#define NFT_OBJECT_COUNTER 1
#define NFT_OBJECT_QUOTA 2
#define NFT_OBJECT_CT_HELPER 3
#define NFT_OBJECT_LIMIT 4
#define NFT_OBJECT_CONNLIMIT 5
-#define __NFT_OBJECT_MAX 6
+#define NFT_OBJECT_CT_TIMEOUT 6
+#define __NFT_OBJECT_MAX 7
#define NFT_OBJECT_MAX (__NFT_OBJECT_MAX - 1)
/**
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 3f211e1025c1..c1cf24b6db96 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -7152,6 +7152,10 @@ static int __net_init nf_tables_init_net(struct net *net)
{
INIT_LIST_HEAD(&net->nft.tables);
INIT_LIST_HEAD(&net->nft.commit_list);
+
+#if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
+ INIT_LIST_HEAD(&net->nfct_timeout_list);
+#endif
net->nft.base_seq = 1;
net->nft.validate_state = NFT_VALIDATE_SKIP;
diff --git a/net/netfilter/nft_ct.c b/net/netfilter/nft_ct.c
index 1435ffc5f57e..c5a0a8edd248 100644
--- a/net/netfilter/nft_ct.c
+++ b/net/netfilter/nft_ct.c
@@ -22,6 +22,9 @@
#include <net/netfilter/nf_conntrack_helper.h>
#include <net/netfilter/nf_conntrack_ecache.h>
#include <net/netfilter/nf_conntrack_labels.h>
+#include <linux/netfilter/nfnetlink_cttimeout.h>
+#include <net/netfilter/nf_conntrack_timeout.h>
+#include <net/netfilter/nf_conntrack_l4proto.h>
struct nft_ct {
enum nft_ct_keys key:8;
@@ -38,6 +41,11 @@ struct nft_ct_helper_obj {
u8 l4proto;
};
+struct nft_ct_timeout_obj {
+ struct ctnl_timeout *timeout;
+ struct nf_conn *tmpl;
+};
+
#ifdef CONFIG_NF_CONNTRACK_ZONES
static DEFINE_PER_CPU(struct nf_conn *, nft_ct_pcpu_template);
static unsigned int nft_ct_pcpu_template_refcnt __read_mostly;
@@ -765,6 +773,159 @@ static struct nft_expr_type nft_notrack_type __read_mostly = {
.owner = THIS_MODULE,
};
+#ifdef CONFIG_NF_CT_NETLINK_TIMEOUT
+static int
+nft_ct_timeout_parse_policy(void *timeouts,
+ const struct nf_conntrack_l4proto *l4proto,
+ struct net *net, const struct nlattr *attr)
+{
+ struct nlattr **tb;
+ int ret = 0;
+
+ if (!l4proto->ctnl_timeout.nlattr_to_obj)
+ return 0;
+
+ tb = kcalloc(l4proto->ctnl_timeout.nlattr_max + 1, sizeof(*tb),
+ GFP_KERNEL);
+
+ if (!tb)
+ return -ENOMEM;
+
+ ret = nla_parse_nested(tb, l4proto->ctnl_timeout.nlattr_max,
+ attr, l4proto->ctnl_timeout.nla_policy,
+ NULL);
+ if (ret < 0)
+ goto err;
+
+ ret = l4proto->ctnl_timeout.nlattr_to_obj(tb, net, timeouts);
+
+err:
+ kfree(tb);
+ return ret;
+}
+
+static void nft_ct_timeout_obj_eval(struct nft_object *obj,
+ struct nft_regs *regs,
+ const struct nft_pktinfo *pkt)
+{
+ const struct nft_ct_timeout_obj *priv = nft_obj_data(obj);
+ struct ctnl_timeout *to_assign = NULL;
+ struct nf_conn_timeout *timeout_ext;
+ struct sk_buff *skb = pkt->skb;
+ enum ip_conntrack_info ctinfo;
+
+ if (nf_ct_get(skb, &ctinfo))
+ return;
+
+ to_assign = priv->timeout;
+ timeout_ext = nf_ct_timeout_find(priv->tmpl);
+ nf_ct_set(skb, priv->tmpl, IP_CT_NEW);
+ rcu_assign_pointer(timeout_ext->timeout, to_assign);
+}
+
+static int nft_ct_timeout_obj_init(const struct nft_ctx *ctx,
+ const struct nlattr * const tb[],
+ struct nft_object *obj)
+{
+ const struct nf_conntrack_zone *zone = &nf_ct_zone_dflt;
+ struct nft_ct_timeout_obj *priv = nft_obj_data(obj);
+ struct ctnl_timeout *timeout;
+ const struct nf_conntrack_l4proto *l4proto;
+ struct nf_conn_timeout *timeout_ext;
+ int l3num = ctx->family;
+ struct nf_conn *tmpl;
+ __u8 l4num;
+ int ret;
+
+ if (!tb[NFTA_CT_TIMEOUT_L3PROTO] ||
+ !tb[NFTA_CT_TIMEOUT_L4PROTO] ||
+ !tb[NFTA_CT_TIMEOUT_DATA])
+ return -EINVAL;
+
+ l3num = ntohs(nla_get_be16(tb[NFTA_CT_TIMEOUT_L3PROTO]));
+ l4num = nla_get_u8(tb[NFTA_CT_TIMEOUT_L4PROTO]);
+ l4proto = nf_ct_l4proto_find_get(l3num, l4num);
+
+ if (l4proto->l4proto != l4num) {
+ ret = -EOPNOTSUPP;
+ goto err_proto_put;
+ }
+
+ timeout = kzalloc(sizeof(struct ctnl_timeout) +
+ l4proto->ctnl_timeout.obj_size, GFP_KERNEL);
+ if (timeout == NULL) {
+ ret = -ENOMEM;
+ goto err_proto_put;
+ }
+
+ ret = nft_ct_timeout_parse_policy(&timeout->data, l4proto, ctx->net,
+ tb[NFTA_CT_TIMEOUT_DATA]);
+ if (ret < 0)
+ goto err;
+ timeout->l3num = l3num;
+ timeout->l4proto = l4proto;
+ priv->timeout = timeout;
+ tmpl = nf_ct_tmpl_alloc(ctx->net, zone, GFP_ATOMIC);
+ if (!tmpl)
+ return -ENOMEM;
+ timeout_ext = nf_ct_timeout_ext_add(tmpl, priv->timeout,
+ GFP_ATOMIC);
+
+ if (!timeout_ext) {
+ nf_ct_tmpl_free(tmpl);
+ return -ENOMEM;
+ }
+
+ priv->tmpl = tmpl;
+ refcount_set(&priv->timeout->refcnt, 1);
+ list_add_tail_rcu(&timeout->head, &ctx->net->nfct_timeout_list);
+ return 0;
+
+err:
+ kfree(timeout);
+err_proto_put:
+ nf_ct_l4proto_put(l4proto);
+ return ret;
+}
+
+static void nft_ct_timeout_obj_destroy(const struct nft_ctx *ctx,
+ struct nft_object *obj)
+{
+ struct nft_ct_timeout_obj *priv = nft_obj_data(obj);
+
+ nf_ct_tmpl_free(priv->tmpl);
+
+ if (refcount_dec_if_one(&priv->timeout->refcnt)) {
+ nf_ct_l4proto_put(priv->timeout->l4proto);
+ list_del_rcu(&priv->timeout->head);
+ nf_ct_untimeout(ctx->net, priv->timeout);
+ }
+}
+
+static int nft_ct_timeout_obj_dump(struct sk_buff *skb,
+ struct nft_object *obj, bool reset)
+{
+ const struct nft_ct_timeout_obj *priv = nft_obj_data(obj);
+ const struct ctnl_timeout *timeout = priv->timeout;
+ struct nlattr *nest_params;
+ int ret;
+
+ if (nla_put_u8(skb, NFTA_CT_TIMEOUT_L4PROTO, timeout->l4proto->l4proto) ||
+ nla_put_be16(skb, NFTA_CT_TIMEOUT_L3PROTO, htons(timeout->l3num)))
+ return -1;
+
+ nest_params = nla_nest_start(skb, NFTA_CT_TIMEOUT_DATA | NLA_F_NESTED);
+ if (!nest_params)
+ return -1;
+
+ ret = timeout->l4proto->ctnl_timeout.obj_to_nlattr(skb, &timeout->data);
+ if (ret < 0)
+ return -1;
+ nla_nest_end(skb, nest_params);
+ return 0;
+}
+#endif
+
static int nft_ct_helper_obj_init(const struct nft_ctx *ctx,
const struct nlattr * const tb[],
struct nft_object *obj)
@@ -932,6 +1093,30 @@ static struct nft_object_type nft_ct_helper_obj_type __read_mostly = {
.owner = THIS_MODULE,
};
+static const struct nla_policy nft_ct_timeout_policy[NFTA_CT_TIMEOUT_MAX + 1] = {
+ [NFTA_CT_TIMEOUT_L3PROTO] = {.type = NLA_U16 },
+ [NFTA_CT_TIMEOUT_L4PROTO] = {.type = NLA_U8 },
+ [NFTA_CT_TIMEOUT_DATA] = {.type = NLA_NESTED },
+};
+
+static struct nft_object_type nft_ct_timeout_obj_type;
+static const struct nft_object_ops nft_ct_timeout_obj_ops = {
+ .type = &nft_ct_timeout_obj_type,
+ .size = sizeof(struct nft_ct_timeout_obj),
+ .eval = nft_ct_timeout_obj_eval,
+ .init = nft_ct_timeout_obj_init,
+ .destroy = nft_ct_timeout_obj_destroy,
+ .dump = nft_ct_timeout_obj_dump,
+};
+
+static struct nft_object_type nft_ct_timeout_obj_type __read_mostly = {
+ .type = NFT_OBJECT_CT_TIMEOUT,
+ .ops = &nft_ct_timeout_obj_ops,
+ .maxattr = NFTA_CT_TIMEOUT_MAX,
+ .policy = nft_ct_timeout_policy,
+ .owner = THIS_MODULE,
+};
+
static int __init nft_ct_module_init(void)
{
int err;
@@ -949,9 +1134,14 @@ static int __init nft_ct_module_init(void)
err = nft_register_obj(&nft_ct_helper_obj_type);
if (err < 0)
goto err2;
+ err = nft_register_obj(&nft_ct_timeout_obj_type);
+ if (err < 0)
+ goto err3;
return 0;
+err3:
+ nft_unregister_obj(&nft_ct_helper_obj_type);
err2:
nft_unregister_expr(&nft_notrack_type);
err1:
@@ -962,6 +1152,7 @@ static int __init nft_ct_module_init(void)
static void __exit nft_ct_module_exit(void)
{
nft_unregister_obj(&nft_ct_helper_obj_type);
+ nft_unregister_obj(&nft_ct_timeout_obj_type);
nft_unregister_expr(&nft_notrack_type);
nft_unregister_expr(&nft_ct_type);
}
@@ -974,3 +1165,4 @@ MODULE_AUTHOR("Patrick McHardy <kaber@xxxxxxxxx>");
MODULE_ALIAS_NFT_EXPR("ct");
MODULE_ALIAS_NFT_EXPR("notrack");
MODULE_ALIAS_NFT_OBJ(NFT_OBJECT_CT_HELPER);
+MODULE_ALIAS_NFT_OBJ(NFT_OBJECT_CT_TIMEOUT);
--
2.14.1
--
To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
