diff options
Diffstat (limited to 'net/sched/act_connmark.c')
| -rw-r--r-- | net/sched/act_connmark.c | 279 |
1 files changed, 279 insertions, 0 deletions
diff --git a/net/sched/act_connmark.c b/net/sched/act_connmark.c new file mode 100644 index 0000000000..0d7aee8933 --- /dev/null +++ b/net/sched/act_connmark.c @@ -0,0 +1,279 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * net/sched/act_connmark.c netfilter connmark retriever action + * skb mark is over-written + * + * Copyright (c) 2011 Felix Fietkau <nbd@openwrt.org> +*/ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/skbuff.h> +#include <linux/rtnetlink.h> +#include <linux/pkt_cls.h> +#include <linux/ip.h> +#include <linux/ipv6.h> +#include <net/netlink.h> +#include <net/pkt_sched.h> +#include <net/act_api.h> +#include <net/pkt_cls.h> +#include <uapi/linux/tc_act/tc_connmark.h> +#include <net/tc_act/tc_connmark.h> +#include <net/tc_wrapper.h> + +#include <net/netfilter/nf_conntrack.h> +#include <net/netfilter/nf_conntrack_core.h> +#include <net/netfilter/nf_conntrack_zones.h> + +static struct tc_action_ops act_connmark_ops; + +TC_INDIRECT_SCOPE int tcf_connmark_act(struct sk_buff *skb, + const struct tc_action *a, + struct tcf_result *res) +{ + const struct nf_conntrack_tuple_hash *thash; + struct nf_conntrack_tuple tuple; + enum ip_conntrack_info ctinfo; + struct tcf_connmark_info *ca = to_connmark(a); + struct tcf_connmark_parms *parms; + struct nf_conntrack_zone zone; + struct nf_conn *c; + int proto; + + tcf_lastuse_update(&ca->tcf_tm); + tcf_action_update_bstats(&ca->common, skb); + + parms = rcu_dereference_bh(ca->parms); + + switch (skb_protocol(skb, true)) { + case htons(ETH_P_IP): + if (skb->len < sizeof(struct iphdr)) + goto out; + + proto = NFPROTO_IPV4; + break; + case htons(ETH_P_IPV6): + if (skb->len < sizeof(struct ipv6hdr)) + goto out; + + proto = NFPROTO_IPV6; + break; + default: + goto out; + } + + c = nf_ct_get(skb, &ctinfo); + if (c) { + skb->mark = READ_ONCE(c->mark); + goto count; + } + + if (!nf_ct_get_tuplepr(skb, skb_network_offset(skb), proto, parms->net, + &tuple)) + goto out; + + zone.id = parms->zone; + zone.dir = NF_CT_DEFAULT_ZONE_DIR; + + thash = nf_conntrack_find_get(parms->net, &zone, &tuple); + if (!thash) + goto out; + + c = nf_ct_tuplehash_to_ctrack(thash); + skb->mark = READ_ONCE(c->mark); + nf_ct_put(c); + +count: + /* using overlimits stats to count how many packets marked */ + tcf_action_inc_overlimit_qstats(&ca->common); +out: + return READ_ONCE(ca->tcf_action); +} + +static const struct nla_policy connmark_policy[TCA_CONNMARK_MAX + 1] = { + [TCA_CONNMARK_PARMS] = { .len = sizeof(struct tc_connmark) }, +}; + +static int tcf_connmark_init(struct net *net, struct nlattr *nla, + struct nlattr *est, struct tc_action **a, + struct tcf_proto *tp, u32 flags, + struct netlink_ext_ack *extack) +{ + struct tc_action_net *tn = net_generic(net, act_connmark_ops.net_id); + struct tcf_connmark_parms *nparms, *oparms; + struct nlattr *tb[TCA_CONNMARK_MAX + 1]; + bool bind = flags & TCA_ACT_FLAGS_BIND; + struct tcf_chain *goto_ch = NULL; + struct tcf_connmark_info *ci; + struct tc_connmark *parm; + int ret = 0, err; + u32 index; + + if (!nla) + return -EINVAL; + + ret = nla_parse_nested_deprecated(tb, TCA_CONNMARK_MAX, nla, + connmark_policy, NULL); + if (ret < 0) + return ret; + + if (!tb[TCA_CONNMARK_PARMS]) + return -EINVAL; + + nparms = kzalloc(sizeof(*nparms), GFP_KERNEL); + if (!nparms) + return -ENOMEM; + + parm = nla_data(tb[TCA_CONNMARK_PARMS]); + index = parm->index; + ret = tcf_idr_check_alloc(tn, &index, a, bind); + if (!ret) { + ret = tcf_idr_create_from_flags(tn, index, est, a, + &act_connmark_ops, bind, flags); + if (ret) { + tcf_idr_cleanup(tn, index); + err = ret; + goto out_free; + } + + ci = to_connmark(*a); + + nparms->net = net; + nparms->zone = parm->zone; + + ret = ACT_P_CREATED; + } else if (ret > 0) { + ci = to_connmark(*a); + if (bind) { + err = 0; + goto out_free; + } + if (!(flags & TCA_ACT_FLAGS_REPLACE)) { + err = -EEXIST; + goto release_idr; + } + + nparms->net = rtnl_dereference(ci->parms)->net; + nparms->zone = parm->zone; + + ret = 0; + } else { + err = ret; + goto out_free; + } + + err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack); + if (err < 0) + goto release_idr; + + spin_lock_bh(&ci->tcf_lock); + goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch); + oparms = rcu_replace_pointer(ci->parms, nparms, lockdep_is_held(&ci->tcf_lock)); + spin_unlock_bh(&ci->tcf_lock); + + if (goto_ch) + tcf_chain_put_by_act(goto_ch); + + if (oparms) + kfree_rcu(oparms, rcu); + + return ret; + +release_idr: + tcf_idr_release(*a, bind); +out_free: + kfree(nparms); + return err; +} + +static inline int tcf_connmark_dump(struct sk_buff *skb, struct tc_action *a, + int bind, int ref) +{ + unsigned char *b = skb_tail_pointer(skb); + struct tcf_connmark_info *ci = to_connmark(a); + struct tc_connmark opt = { + .index = ci->tcf_index, + .refcnt = refcount_read(&ci->tcf_refcnt) - ref, + .bindcnt = atomic_read(&ci->tcf_bindcnt) - bind, + }; + struct tcf_connmark_parms *parms; + struct tcf_t t; + + spin_lock_bh(&ci->tcf_lock); + parms = rcu_dereference_protected(ci->parms, lockdep_is_held(&ci->tcf_lock)); + + opt.action = ci->tcf_action; + opt.zone = parms->zone; + if (nla_put(skb, TCA_CONNMARK_PARMS, sizeof(opt), &opt)) + goto nla_put_failure; + + tcf_tm_dump(&t, &ci->tcf_tm); + if (nla_put_64bit(skb, TCA_CONNMARK_TM, sizeof(t), &t, + TCA_CONNMARK_PAD)) + goto nla_put_failure; + spin_unlock_bh(&ci->tcf_lock); + + return skb->len; + +nla_put_failure: + spin_unlock_bh(&ci->tcf_lock); + nlmsg_trim(skb, b); + return -1; +} + +static void tcf_connmark_cleanup(struct tc_action *a) +{ + struct tcf_connmark_info *ci = to_connmark(a); + struct tcf_connmark_parms *parms; + + parms = rcu_dereference_protected(ci->parms, 1); + if (parms) + kfree_rcu(parms, rcu); +} + +static struct tc_action_ops act_connmark_ops = { + .kind = "connmark", + .id = TCA_ID_CONNMARK, + .owner = THIS_MODULE, + .act = tcf_connmark_act, + .dump = tcf_connmark_dump, + .init = tcf_connmark_init, + .cleanup = tcf_connmark_cleanup, + .size = sizeof(struct tcf_connmark_info), +}; + +static __net_init int connmark_init_net(struct net *net) +{ + struct tc_action_net *tn = net_generic(net, act_connmark_ops.net_id); + + return tc_action_net_init(net, tn, &act_connmark_ops); +} + +static void __net_exit connmark_exit_net(struct list_head *net_list) +{ + tc_action_net_exit(net_list, act_connmark_ops.net_id); +} + +static struct pernet_operations connmark_net_ops = { + .init = connmark_init_net, + .exit_batch = connmark_exit_net, + .id = &act_connmark_ops.net_id, + .size = sizeof(struct tc_action_net), +}; + +static int __init connmark_init_module(void) +{ + return tcf_register_action(&act_connmark_ops, &connmark_net_ops); +} + +static void __exit connmark_cleanup_module(void) +{ + tcf_unregister_action(&act_connmark_ops, &connmark_net_ops); +} + +module_init(connmark_init_module); +module_exit(connmark_cleanup_module); +MODULE_AUTHOR("Felix Fietkau <nbd@openwrt.org>"); +MODULE_DESCRIPTION("Connection tracking mark restoring"); +MODULE_LICENSE("GPL"); |