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13#include <linux/module.h>
14#include <linux/init.h>
15#include <linux/kernel.h>
16#include <linux/skbuff.h>
17#include <linux/rtnetlink.h>
18#include <linux/pkt_cls.h>
19#include <linux/ip.h>
20#include <linux/ipv6.h>
21#include <net/netlink.h>
22#include <net/pkt_sched.h>
23#include <net/act_api.h>
24#include <uapi/linux/tc_act/tc_connmark.h>
25#include <net/tc_act/tc_connmark.h>
26
27#include <net/netfilter/nf_conntrack.h>
28#include <net/netfilter/nf_conntrack_core.h>
29#include <net/netfilter/nf_conntrack_zones.h>
30
31#define CONNMARK_TAB_MASK 3
32
33static unsigned int connmark_net_id;
34static struct tc_action_ops act_connmark_ops;
35
36static int tcf_connmark(struct sk_buff *skb, const struct tc_action *a,
37 struct tcf_result *res)
38{
39 const struct nf_conntrack_tuple_hash *thash;
40 struct nf_conntrack_tuple tuple;
41 enum ip_conntrack_info ctinfo;
42 struct tcf_connmark_info *ca = to_connmark(a);
43 struct nf_conntrack_zone zone;
44 struct nf_conn *c;
45 int proto;
46
47 spin_lock(&ca->tcf_lock);
48 tcf_lastuse_update(&ca->tcf_tm);
49 bstats_update(&ca->tcf_bstats, skb);
50
51 if (skb->protocol == htons(ETH_P_IP)) {
52 if (skb->len < sizeof(struct iphdr))
53 goto out;
54
55 proto = NFPROTO_IPV4;
56 } else if (skb->protocol == htons(ETH_P_IPV6)) {
57 if (skb->len < sizeof(struct ipv6hdr))
58 goto out;
59
60 proto = NFPROTO_IPV6;
61 } else {
62 goto out;
63 }
64
65 c = nf_ct_get(skb, &ctinfo);
66 if (c) {
67 skb->mark = c->mark;
68
69 ca->tcf_qstats.overlimits++;
70 goto out;
71 }
72
73 if (!nf_ct_get_tuplepr(skb, skb_network_offset(skb),
74 proto, ca->net, &tuple))
75 goto out;
76
77 zone.id = ca->zone;
78 zone.dir = NF_CT_DEFAULT_ZONE_DIR;
79
80 thash = nf_conntrack_find_get(ca->net, &zone, &tuple);
81 if (!thash)
82 goto out;
83
84 c = nf_ct_tuplehash_to_ctrack(thash);
85
86 ca->tcf_qstats.overlimits++;
87 skb->mark = c->mark;
88 nf_ct_put(c);
89
90out:
91 spin_unlock(&ca->tcf_lock);
92 return ca->tcf_action;
93}
94
95static const struct nla_policy connmark_policy[TCA_CONNMARK_MAX + 1] = {
96 [TCA_CONNMARK_PARMS] = { .len = sizeof(struct tc_connmark) },
97};
98
99static int tcf_connmark_init(struct net *net, struct nlattr *nla,
100 struct nlattr *est, struct tc_action **a,
101 int ovr, int bind)
102{
103 struct tc_action_net *tn = net_generic(net, connmark_net_id);
104 struct nlattr *tb[TCA_CONNMARK_MAX + 1];
105 struct tcf_connmark_info *ci;
106 struct tc_connmark *parm;
107 int ret = 0;
108
109 if (!nla)
110 return -EINVAL;
111
112 ret = nla_parse_nested(tb, TCA_CONNMARK_MAX, nla, connmark_policy,
113 NULL);
114 if (ret < 0)
115 return ret;
116
117 if (!tb[TCA_CONNMARK_PARMS])
118 return -EINVAL;
119
120 parm = nla_data(tb[TCA_CONNMARK_PARMS]);
121
122 if (!tcf_hash_check(tn, parm->index, a, bind)) {
123 ret = tcf_hash_create(tn, parm->index, est, a,
124 &act_connmark_ops, bind, false);
125 if (ret)
126 return ret;
127
128 ci = to_connmark(*a);
129 ci->tcf_action = parm->action;
130 ci->net = net;
131 ci->zone = parm->zone;
132
133 tcf_hash_insert(tn, *a);
134 ret = ACT_P_CREATED;
135 } else {
136 ci = to_connmark(*a);
137 if (bind)
138 return 0;
139 tcf_hash_release(*a, bind);
140 if (!ovr)
141 return -EEXIST;
142
143 ci->tcf_action = parm->action;
144 ci->zone = parm->zone;
145 }
146
147 return ret;
148}
149
150static inline int tcf_connmark_dump(struct sk_buff *skb, struct tc_action *a,
151 int bind, int ref)
152{
153 unsigned char *b = skb_tail_pointer(skb);
154 struct tcf_connmark_info *ci = to_connmark(a);
155
156 struct tc_connmark opt = {
157 .index = ci->tcf_index,
158 .refcnt = ci->tcf_refcnt - ref,
159 .bindcnt = ci->tcf_bindcnt - bind,
160 .action = ci->tcf_action,
161 .zone = ci->zone,
162 };
163 struct tcf_t t;
164
165 if (nla_put(skb, TCA_CONNMARK_PARMS, sizeof(opt), &opt))
166 goto nla_put_failure;
167
168 tcf_tm_dump(&t, &ci->tcf_tm);
169 if (nla_put_64bit(skb, TCA_CONNMARK_TM, sizeof(t), &t,
170 TCA_CONNMARK_PAD))
171 goto nla_put_failure;
172
173 return skb->len;
174nla_put_failure:
175 nlmsg_trim(skb, b);
176 return -1;
177}
178
179static int tcf_connmark_walker(struct net *net, struct sk_buff *skb,
180 struct netlink_callback *cb, int type,
181 const struct tc_action_ops *ops)
182{
183 struct tc_action_net *tn = net_generic(net, connmark_net_id);
184
185 return tcf_generic_walker(tn, skb, cb, type, ops);
186}
187
188static int tcf_connmark_search(struct net *net, struct tc_action **a, u32 index)
189{
190 struct tc_action_net *tn = net_generic(net, connmark_net_id);
191
192 return tcf_hash_search(tn, a, index);
193}
194
195static struct tc_action_ops act_connmark_ops = {
196 .kind = "connmark",
197 .type = TCA_ACT_CONNMARK,
198 .owner = THIS_MODULE,
199 .act = tcf_connmark,
200 .dump = tcf_connmark_dump,
201 .init = tcf_connmark_init,
202 .walk = tcf_connmark_walker,
203 .lookup = tcf_connmark_search,
204 .size = sizeof(struct tcf_connmark_info),
205};
206
207static __net_init int connmark_init_net(struct net *net)
208{
209 struct tc_action_net *tn = net_generic(net, connmark_net_id);
210
211 return tc_action_net_init(tn, &act_connmark_ops, CONNMARK_TAB_MASK);
212}
213
214static void __net_exit connmark_exit_net(struct net *net)
215{
216 struct tc_action_net *tn = net_generic(net, connmark_net_id);
217
218 tc_action_net_exit(tn);
219}
220
221static struct pernet_operations connmark_net_ops = {
222 .init = connmark_init_net,
223 .exit = connmark_exit_net,
224 .id = &connmark_net_id,
225 .size = sizeof(struct tc_action_net),
226};
227
228static int __init connmark_init_module(void)
229{
230 return tcf_register_action(&act_connmark_ops, &connmark_net_ops);
231}
232
233static void __exit connmark_cleanup_module(void)
234{
235 tcf_unregister_action(&act_connmark_ops, &connmark_net_ops);
236}
237
238module_init(connmark_init_module);
239module_exit(connmark_cleanup_module);
240MODULE_AUTHOR("Felix Fietkau <nbd@openwrt.org>");
241MODULE_DESCRIPTION("Connection tracking mark restoring");
242MODULE_LICENSE("GPL");
243
244
