#include <linux/tcp.h>
#include <linux/udp.h>
#include <linux/sctp.h>
+#include <linux/static_key.h>
#include <net/ip.h>
+#include <net/genetlink.h>
#include <net/netfilter/nf_conntrack_core.h>
+#include <net/netfilter/nf_conntrack_count.h>
#include <net/netfilter/nf_conntrack_helper.h>
#include <net/netfilter/nf_conntrack_labels.h>
#include <net/netfilter/nf_conntrack_seqadj.h>
#endif
};
+#if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
+#define OVS_CT_LIMIT_UNLIMITED 0
+#define OVS_CT_LIMIT_DEFAULT OVS_CT_LIMIT_UNLIMITED
+#define CT_LIMIT_HASH_BUCKETS 512
+static DEFINE_STATIC_KEY_FALSE(ovs_ct_limit_enabled);
+
+struct ovs_ct_limit {
+ /* Elements in ovs_ct_limit_info->limits hash table */
+ struct hlist_node hlist_node;
+ struct rcu_head rcu;
+ u16 zone;
+ u32 limit;
+};
+
+struct ovs_ct_limit_info {
+ u32 default_limit;
+ struct hlist_head *limits;
+ struct nf_conncount_data *data;
+};
+
+static const struct nla_policy ct_limit_policy[OVS_CT_LIMIT_ATTR_MAX + 1] = {
+ [OVS_CT_LIMIT_ATTR_ZONE_LIMIT] = { .type = NLA_NESTED, },
+};
+#endif
+
static bool labels_nonzero(const struct ovs_key_ct_labels *labels);
static void __ovs_ct_free_action(struct ovs_conntrack_info *ct_info);
return false;
}
+#if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
+static struct hlist_head *ct_limit_hash_bucket(
+ const struct ovs_ct_limit_info *info, u16 zone)
+{
+ return &info->limits[zone & (CT_LIMIT_HASH_BUCKETS - 1)];
+}
+
+/* Call with ovs_mutex */
+static void ct_limit_set(const struct ovs_ct_limit_info *info,
+ struct ovs_ct_limit *new_ct_limit)
+{
+ struct ovs_ct_limit *ct_limit;
+ struct hlist_head *head;
+
+ head = ct_limit_hash_bucket(info, new_ct_limit->zone);
+ hlist_for_each_entry_rcu(ct_limit, head, hlist_node) {
+ if (ct_limit->zone == new_ct_limit->zone) {
+ hlist_replace_rcu(&ct_limit->hlist_node,
+ &new_ct_limit->hlist_node);
+ kfree_rcu(ct_limit, rcu);
+ return;
+ }
+ }
+
+ hlist_add_head_rcu(&new_ct_limit->hlist_node, head);
+}
+
+/* Call with ovs_mutex */
+static void ct_limit_del(const struct ovs_ct_limit_info *info, u16 zone)
+{
+ struct ovs_ct_limit *ct_limit;
+ struct hlist_head *head;
+ struct hlist_node *n;
+
+ head = ct_limit_hash_bucket(info, zone);
+ hlist_for_each_entry_safe(ct_limit, n, head, hlist_node) {
+ if (ct_limit->zone == zone) {
+ hlist_del_rcu(&ct_limit->hlist_node);
+ kfree_rcu(ct_limit, rcu);
+ return;
+ }
+ }
+}
+
+/* Call with RCU read lock */
+static u32 ct_limit_get(const struct ovs_ct_limit_info *info, u16 zone)
+{
+ struct ovs_ct_limit *ct_limit;
+ struct hlist_head *head;
+
+ head = ct_limit_hash_bucket(info, zone);
+ hlist_for_each_entry_rcu(ct_limit, head, hlist_node) {
+ if (ct_limit->zone == zone)
+ return ct_limit->limit;
+ }
+
+ return info->default_limit;
+}
+
+static int ovs_ct_check_limit(struct net *net,
+ const struct ovs_conntrack_info *info,
+ const struct nf_conntrack_tuple *tuple)
+{
+ struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
+ const struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info;
+ u32 per_zone_limit, connections;
+ u32 conncount_key;
+
+ conncount_key = info->zone.id;
+
+ per_zone_limit = ct_limit_get(ct_limit_info, info->zone.id);
+ if (per_zone_limit == OVS_CT_LIMIT_UNLIMITED)
+ return 0;
+
+ connections = nf_conncount_count(net, ct_limit_info->data,
+ &conncount_key, tuple, &info->zone);
+ if (connections > per_zone_limit)
+ return -ENOMEM;
+
+ return 0;
+}
+#endif
+
/* Lookup connection and confirm if unconfirmed. */
static int ovs_ct_commit(struct net *net, struct sw_flow_key *key,
const struct ovs_conntrack_info *info,
if (!ct)
return 0;
+#if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
+ if (static_branch_unlikely(&ovs_ct_limit_enabled)) {
+ if (!nf_ct_is_confirmed(ct)) {
+ err = ovs_ct_check_limit(net, info,
+ &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
+ if (err) {
+ net_warn_ratelimited("openvswitch: zone: %u "
+ "execeeds conntrack limit\n",
+ info->zone.id);
+ return err;
+ }
+ }
+ }
+#endif
+
/* Set the conntrack event mask if given. NEW and DELETE events have
* their own groups, but the NFNLGRP_CONNTRACK_UPDATE group listener
* typically would receive many kinds of updates. Setting the event
nf_ct_tmpl_free(ct_info->ct);
}
-void ovs_ct_init(struct net *net)
+#if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
+static int ovs_ct_limit_init(struct net *net, struct ovs_net *ovs_net)
+{
+ int i, err;
+
+ ovs_net->ct_limit_info = kmalloc(sizeof(*ovs_net->ct_limit_info),
+ GFP_KERNEL);
+ if (!ovs_net->ct_limit_info)
+ return -ENOMEM;
+
+ ovs_net->ct_limit_info->default_limit = OVS_CT_LIMIT_DEFAULT;
+ ovs_net->ct_limit_info->limits =
+ kmalloc_array(CT_LIMIT_HASH_BUCKETS, sizeof(struct hlist_head),
+ GFP_KERNEL);
+ if (!ovs_net->ct_limit_info->limits) {
+ kfree(ovs_net->ct_limit_info);
+ return -ENOMEM;
+ }
+
+ for (i = 0; i < CT_LIMIT_HASH_BUCKETS; i++)
+ INIT_HLIST_HEAD(&ovs_net->ct_limit_info->limits[i]);
+
+ ovs_net->ct_limit_info->data =
+ nf_conncount_init(net, NFPROTO_INET, sizeof(u32));
+
+ if (IS_ERR(ovs_net->ct_limit_info->data)) {
+ err = PTR_ERR(ovs_net->ct_limit_info->data);
+ kfree(ovs_net->ct_limit_info->limits);
+ kfree(ovs_net->ct_limit_info);
+ pr_err("openvswitch: failed to init nf_conncount %d\n", err);
+ return err;
+ }
+ return 0;
+}
+
+static void ovs_ct_limit_exit(struct net *net, struct ovs_net *ovs_net)
+{
+ const struct ovs_ct_limit_info *info = ovs_net->ct_limit_info;
+ int i;
+
+ nf_conncount_destroy(net, NFPROTO_INET, info->data);
+ for (i = 0; i < CT_LIMIT_HASH_BUCKETS; ++i) {
+ struct hlist_head *head = &info->limits[i];
+ struct ovs_ct_limit *ct_limit;
+
+ hlist_for_each_entry_rcu(ct_limit, head, hlist_node)
+ kfree_rcu(ct_limit, rcu);
+ }
+ kfree(ovs_net->ct_limit_info->limits);
+ kfree(ovs_net->ct_limit_info);
+}
+
+static struct sk_buff *
+ovs_ct_limit_cmd_reply_start(struct genl_info *info, u8 cmd,
+ struct ovs_header **ovs_reply_header)
+{
+ struct ovs_header *ovs_header = info->userhdr;
+ struct sk_buff *skb;
+
+ skb = genlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
+ if (!skb)
+ return ERR_PTR(-ENOMEM);
+
+ *ovs_reply_header = genlmsg_put(skb, info->snd_portid,
+ info->snd_seq,
+ &dp_ct_limit_genl_family, 0, cmd);
+
+ if (!*ovs_reply_header) {
+ nlmsg_free(skb);
+ return ERR_PTR(-EMSGSIZE);
+ }
+ (*ovs_reply_header)->dp_ifindex = ovs_header->dp_ifindex;
+
+ return skb;
+}
+
+static bool check_zone_id(int zone_id, u16 *pzone)
+{
+ if (zone_id >= 0 && zone_id <= 65535) {
+ *pzone = (u16)zone_id;
+ return true;
+ }
+ return false;
+}
+
+static int ovs_ct_limit_set_zone_limit(struct nlattr *nla_zone_limit,
+ struct ovs_ct_limit_info *info)
+{
+ struct ovs_zone_limit *zone_limit;
+ int rem;
+ u16 zone;
+
+ rem = NLA_ALIGN(nla_len(nla_zone_limit));
+ zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit);
+
+ while (rem >= sizeof(*zone_limit)) {
+ if (unlikely(zone_limit->zone_id ==
+ OVS_ZONE_LIMIT_DEFAULT_ZONE)) {
+ ovs_lock();
+ info->default_limit = zone_limit->limit;
+ ovs_unlock();
+ } else if (unlikely(!check_zone_id(
+ zone_limit->zone_id, &zone))) {
+ OVS_NLERR(true, "zone id is out of range");
+ } else {
+ struct ovs_ct_limit *ct_limit;
+
+ ct_limit = kmalloc(sizeof(*ct_limit), GFP_KERNEL);
+ if (!ct_limit)
+ return -ENOMEM;
+
+ ct_limit->zone = zone;
+ ct_limit->limit = zone_limit->limit;
+
+ ovs_lock();
+ ct_limit_set(info, ct_limit);
+ ovs_unlock();
+ }
+ rem -= NLA_ALIGN(sizeof(*zone_limit));
+ zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit +
+ NLA_ALIGN(sizeof(*zone_limit)));
+ }
+
+ if (rem)
+ OVS_NLERR(true, "set zone limit has %d unknown bytes", rem);
+
+ return 0;
+}
+
+static int ovs_ct_limit_del_zone_limit(struct nlattr *nla_zone_limit,
+ struct ovs_ct_limit_info *info)
+{
+ struct ovs_zone_limit *zone_limit;
+ int rem;
+ u16 zone;
+
+ rem = NLA_ALIGN(nla_len(nla_zone_limit));
+ zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit);
+
+ while (rem >= sizeof(*zone_limit)) {
+ if (unlikely(zone_limit->zone_id ==
+ OVS_ZONE_LIMIT_DEFAULT_ZONE)) {
+ ovs_lock();
+ info->default_limit = OVS_CT_LIMIT_DEFAULT;
+ ovs_unlock();
+ } else if (unlikely(!check_zone_id(
+ zone_limit->zone_id, &zone))) {
+ OVS_NLERR(true, "zone id is out of range");
+ } else {
+ ovs_lock();
+ ct_limit_del(info, zone);
+ ovs_unlock();
+ }
+ rem -= NLA_ALIGN(sizeof(*zone_limit));
+ zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit +
+ NLA_ALIGN(sizeof(*zone_limit)));
+ }
+
+ if (rem)
+ OVS_NLERR(true, "del zone limit has %d unknown bytes", rem);
+
+ return 0;
+}
+
+static int ovs_ct_limit_get_default_limit(struct ovs_ct_limit_info *info,
+ struct sk_buff *reply)
+{
+ struct ovs_zone_limit zone_limit;
+ int err;
+
+ zone_limit.zone_id = OVS_ZONE_LIMIT_DEFAULT_ZONE;
+ zone_limit.limit = info->default_limit;
+ err = nla_put_nohdr(reply, sizeof(zone_limit), &zone_limit);
+ if (err)
+ return err;
+
+ return 0;
+}
+
+static int __ovs_ct_limit_get_zone_limit(struct net *net,
+ struct nf_conncount_data *data,
+ u16 zone_id, u32 limit,
+ struct sk_buff *reply)
+{
+ struct nf_conntrack_zone ct_zone;
+ struct ovs_zone_limit zone_limit;
+ u32 conncount_key = zone_id;
+
+ zone_limit.zone_id = zone_id;
+ zone_limit.limit = limit;
+ nf_ct_zone_init(&ct_zone, zone_id, NF_CT_DEFAULT_ZONE_DIR, 0);
+
+ zone_limit.count = nf_conncount_count(net, data, &conncount_key, NULL,
+ &ct_zone);
+ return nla_put_nohdr(reply, sizeof(zone_limit), &zone_limit);
+}
+
+static int ovs_ct_limit_get_zone_limit(struct net *net,
+ struct nlattr *nla_zone_limit,
+ struct ovs_ct_limit_info *info,
+ struct sk_buff *reply)
+{
+ struct ovs_zone_limit *zone_limit;
+ int rem, err;
+ u32 limit;
+ u16 zone;
+
+ rem = NLA_ALIGN(nla_len(nla_zone_limit));
+ zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit);
+
+ while (rem >= sizeof(*zone_limit)) {
+ if (unlikely(zone_limit->zone_id ==
+ OVS_ZONE_LIMIT_DEFAULT_ZONE)) {
+ err = ovs_ct_limit_get_default_limit(info, reply);
+ if (err)
+ return err;
+ } else if (unlikely(!check_zone_id(zone_limit->zone_id,
+ &zone))) {
+ OVS_NLERR(true, "zone id is out of range");
+ } else {
+ rcu_read_lock();
+ limit = ct_limit_get(info, zone);
+ rcu_read_unlock();
+
+ err = __ovs_ct_limit_get_zone_limit(
+ net, info->data, zone, limit, reply);
+ if (err)
+ return err;
+ }
+ rem -= NLA_ALIGN(sizeof(*zone_limit));
+ zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit +
+ NLA_ALIGN(sizeof(*zone_limit)));
+ }
+
+ if (rem)
+ OVS_NLERR(true, "get zone limit has %d unknown bytes", rem);
+
+ return 0;
+}
+
+static int ovs_ct_limit_get_all_zone_limit(struct net *net,
+ struct ovs_ct_limit_info *info,
+ struct sk_buff *reply)
+{
+ struct ovs_ct_limit *ct_limit;
+ struct hlist_head *head;
+ int i, err = 0;
+
+ err = ovs_ct_limit_get_default_limit(info, reply);
+ if (err)
+ return err;
+
+ rcu_read_lock();
+ for (i = 0; i < CT_LIMIT_HASH_BUCKETS; ++i) {
+ head = &info->limits[i];
+ hlist_for_each_entry_rcu(ct_limit, head, hlist_node) {
+ err = __ovs_ct_limit_get_zone_limit(net, info->data,
+ ct_limit->zone, ct_limit->limit, reply);
+ if (err)
+ goto exit_err;
+ }
+ }
+
+exit_err:
+ rcu_read_unlock();
+ return err;
+}
+
+static int ovs_ct_limit_cmd_set(struct sk_buff *skb, struct genl_info *info)
+{
+ struct nlattr **a = info->attrs;
+ struct sk_buff *reply;
+ struct ovs_header *ovs_reply_header;
+ struct ovs_net *ovs_net = net_generic(sock_net(skb->sk), ovs_net_id);
+ struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info;
+ int err;
+
+ reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_SET,
+ &ovs_reply_header);
+ if (IS_ERR(reply))
+ return PTR_ERR(reply);
+
+ if (!a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) {
+ err = -EINVAL;
+ goto exit_err;
+ }
+
+ err = ovs_ct_limit_set_zone_limit(a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT],
+ ct_limit_info);
+ if (err)
+ goto exit_err;
+
+ static_branch_enable(&ovs_ct_limit_enabled);
+
+ genlmsg_end(reply, ovs_reply_header);
+ return genlmsg_reply(reply, info);
+
+exit_err:
+ nlmsg_free(reply);
+ return err;
+}
+
+static int ovs_ct_limit_cmd_del(struct sk_buff *skb, struct genl_info *info)
+{
+ struct nlattr **a = info->attrs;
+ struct sk_buff *reply;
+ struct ovs_header *ovs_reply_header;
+ struct ovs_net *ovs_net = net_generic(sock_net(skb->sk), ovs_net_id);
+ struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info;
+ int err;
+
+ reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_DEL,
+ &ovs_reply_header);
+ if (IS_ERR(reply))
+ return PTR_ERR(reply);
+
+ if (!a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) {
+ err = -EINVAL;
+ goto exit_err;
+ }
+
+ err = ovs_ct_limit_del_zone_limit(a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT],
+ ct_limit_info);
+ if (err)
+ goto exit_err;
+
+ genlmsg_end(reply, ovs_reply_header);
+ return genlmsg_reply(reply, info);
+
+exit_err:
+ nlmsg_free(reply);
+ return err;
+}
+
+static int ovs_ct_limit_cmd_get(struct sk_buff *skb, struct genl_info *info)
+{
+ struct nlattr **a = info->attrs;
+ struct nlattr *nla_reply;
+ struct sk_buff *reply;
+ struct ovs_header *ovs_reply_header;
+ struct net *net = sock_net(skb->sk);
+ struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
+ struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info;
+ int err;
+
+ reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_GET,
+ &ovs_reply_header);
+ if (IS_ERR(reply))
+ return PTR_ERR(reply);
+
+ nla_reply = nla_nest_start(reply, OVS_CT_LIMIT_ATTR_ZONE_LIMIT);
+
+ if (a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) {
+ err = ovs_ct_limit_get_zone_limit(
+ net, a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT], ct_limit_info,
+ reply);
+ if (err)
+ goto exit_err;
+ } else {
+ err = ovs_ct_limit_get_all_zone_limit(net, ct_limit_info,
+ reply);
+ if (err)
+ goto exit_err;
+ }
+
+ nla_nest_end(reply, nla_reply);
+ genlmsg_end(reply, ovs_reply_header);
+ return genlmsg_reply(reply, info);
+
+exit_err:
+ nlmsg_free(reply);
+ return err;
+}
+
+static struct genl_ops ct_limit_genl_ops[] = {
+ { .cmd = OVS_CT_LIMIT_CMD_SET,
+ .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN
+ * privilege. */
+ .policy = ct_limit_policy,
+ .doit = ovs_ct_limit_cmd_set,
+ },
+ { .cmd = OVS_CT_LIMIT_CMD_DEL,
+ .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN
+ * privilege. */
+ .policy = ct_limit_policy,
+ .doit = ovs_ct_limit_cmd_del,
+ },
+ { .cmd = OVS_CT_LIMIT_CMD_GET,
+ .flags = 0, /* OK for unprivileged users. */
+ .policy = ct_limit_policy,
+ .doit = ovs_ct_limit_cmd_get,
+ },
+};
+
+static const struct genl_multicast_group ovs_ct_limit_multicast_group = {
+ .name = OVS_CT_LIMIT_MCGROUP,
+};
+
+struct genl_family dp_ct_limit_genl_family __ro_after_init = {
+ .hdrsize = sizeof(struct ovs_header),
+ .name = OVS_CT_LIMIT_FAMILY,
+ .version = OVS_CT_LIMIT_VERSION,
+ .maxattr = OVS_CT_LIMIT_ATTR_MAX,
+ .netnsok = true,
+ .parallel_ops = true,
+ .ops = ct_limit_genl_ops,
+ .n_ops = ARRAY_SIZE(ct_limit_genl_ops),
+ .mcgrps = &ovs_ct_limit_multicast_group,
+ .n_mcgrps = 1,
+ .module = THIS_MODULE,
+};
+#endif
+
+int ovs_ct_init(struct net *net)
{
unsigned int n_bits = sizeof(struct ovs_key_ct_labels) * BITS_PER_BYTE;
struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
} else {
ovs_net->xt_label = true;
}
+
+#if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
+ return ovs_ct_limit_init(net, ovs_net);
+#else
+ return 0;
+#endif
}
void ovs_ct_exit(struct net *net)
{
struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
+#if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
+ ovs_ct_limit_exit(net, ovs_net);
+#endif
+
if (ovs_net->xt_label)
nf_connlabels_put(net);
}