netfilter: add cttimeout infrastructure for fine timeout tuning
This patch adds the infrastructure to add fine timeout tuning
over nfnetlink. Now you can use the NFNL_SUBSYS_CTNETLINK_TIMEOUT
subsystem to create/delete/dump timeout objects that contain some
specific timeout policy for one flow.
The follow up patches will allow you attach timeout policy object
to conntrack via the CT target and the conntrack extension
infrastructure.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
diff --git a/net/netfilter/nf_conntrack_proto_udp.c b/net/netfilter/nf_conntrack_proto_udp.c
index 70e0059..a9073dc 100644
--- a/net/netfilter/nf_conntrack_proto_udp.c
+++ b/net/netfilter/nf_conntrack_proto_udp.c
@@ -152,6 +152,52 @@
return NF_ACCEPT;
}
+#if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
+
+#include <linux/netfilter/nfnetlink.h>
+#include <linux/netfilter/nfnetlink_cttimeout.h>
+
+static int udp_timeout_nlattr_to_obj(struct nlattr *tb[], void *data)
+{
+ unsigned int *timeouts = data;
+
+ /* set default timeouts for UDP. */
+ timeouts[UDP_CT_UNREPLIED] = udp_timeouts[UDP_CT_UNREPLIED];
+ timeouts[UDP_CT_REPLIED] = udp_timeouts[UDP_CT_REPLIED];
+
+ if (tb[CTA_TIMEOUT_UDP_UNREPLIED]) {
+ timeouts[UDP_CT_UNREPLIED] =
+ ntohl(nla_get_be32(tb[CTA_TIMEOUT_UDP_UNREPLIED])) * HZ;
+ }
+ if (tb[CTA_TIMEOUT_UDP_REPLIED]) {
+ timeouts[UDP_CT_REPLIED] =
+ ntohl(nla_get_be32(tb[CTA_TIMEOUT_UDP_REPLIED])) * HZ;
+ }
+ return 0;
+}
+
+static int
+udp_timeout_obj_to_nlattr(struct sk_buff *skb, const void *data)
+{
+ const unsigned int *timeouts = data;
+
+ NLA_PUT_BE32(skb, CTA_TIMEOUT_UDP_UNREPLIED,
+ htonl(timeouts[UDP_CT_UNREPLIED] / HZ));
+ NLA_PUT_BE32(skb, CTA_TIMEOUT_UDP_REPLIED,
+ htonl(timeouts[UDP_CT_REPLIED] / HZ));
+ return 0;
+
+nla_put_failure:
+ return -ENOSPC;
+}
+
+static const struct nla_policy
+udp_timeout_nla_policy[CTA_TIMEOUT_UDP_MAX+1] = {
+ [CTA_TIMEOUT_UDP_UNREPLIED] = { .type = NLA_U32 },
+ [CTA_TIMEOUT_UDP_REPLIED] = { .type = NLA_U32 },
+};
+#endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
+
#ifdef CONFIG_SYSCTL
static unsigned int udp_sysctl_table_users;
static struct ctl_table_header *udp_sysctl_header;
@@ -211,6 +257,15 @@
.nlattr_tuple_size = nf_ct_port_nlattr_tuple_size,
.nla_policy = nf_ct_port_nla_policy,
#endif
+#if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
+ .ctnl_timeout = {
+ .nlattr_to_obj = udp_timeout_nlattr_to_obj,
+ .obj_to_nlattr = udp_timeout_obj_to_nlattr,
+ .nlattr_max = CTA_TIMEOUT_UDP_MAX,
+ .obj_size = sizeof(unsigned int) * CTA_TIMEOUT_UDP_MAX,
+ .nla_policy = udp_timeout_nla_policy,
+ },
+#endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
#ifdef CONFIG_SYSCTL
.ctl_table_users = &udp_sysctl_table_users,
.ctl_table_header = &udp_sysctl_header,
@@ -240,6 +295,15 @@
.nlattr_tuple_size = nf_ct_port_nlattr_tuple_size,
.nla_policy = nf_ct_port_nla_policy,
#endif
+#if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
+ .ctnl_timeout = {
+ .nlattr_to_obj = udp_timeout_nlattr_to_obj,
+ .obj_to_nlattr = udp_timeout_obj_to_nlattr,
+ .nlattr_max = CTA_TIMEOUT_UDP_MAX,
+ .obj_size = sizeof(unsigned int) * CTA_TIMEOUT_UDP_MAX,
+ .nla_policy = udp_timeout_nla_policy,
+ },
+#endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
#ifdef CONFIG_SYSCTL
.ctl_table_users = &udp_sysctl_table_users,
.ctl_table_header = &udp_sysctl_header,