diff options
Diffstat (limited to 'net/openvswitch/conntrack.c')
| -rw-r--r-- | net/openvswitch/conntrack.c | 555 |
1 files changed, 552 insertions, 3 deletions
diff --git a/net/openvswitch/conntrack.c b/net/openvswitch/conntrack.c index c5904f629091d..284aca2a252df 100644 --- a/net/openvswitch/conntrack.c +++ b/net/openvswitch/conntrack.c @@ -16,8 +16,11 @@ #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> @@ -72,10 +75,35 @@ struct ovs_conntrack_info { struct md_mark mark; struct md_labels labels; #ifdef CONFIG_NF_NAT_NEEDED - struct nf_nat_range range; /* Only present for SRC NAT and DST NAT. */ + struct nf_nat_range2 range; /* Only present for SRC NAT and DST NAT. */ #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); @@ -710,7 +738,7 @@ static bool skb_nfct_cached(struct net *net, */ static int ovs_ct_nat_execute(struct sk_buff *skb, struct nf_conn *ct, enum ip_conntrack_info ctinfo, - const struct nf_nat_range *range, + const struct nf_nat_range2 *range, enum nf_nat_manip_type maniptype) { int hooknum, nh_off, err = NF_ACCEPT; @@ -1036,6 +1064,89 @@ static bool labels_nonzero(const struct ovs_key_ct_labels *labels) 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, @@ -1054,6 +1165,21 @@ static int ovs_ct_commit(struct net *net, struct sw_flow_key *key, 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 @@ -1655,7 +1781,420 @@ static void __ovs_ct_free_action(struct ovs_conntrack_info *ct_info) 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); @@ -1666,12 +2205,22 @@ void ovs_ct_init(struct net *net) } 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); } |