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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 int tcf_connmark(struct sk_buff *skb, const struct tc_action *a,
34 struct tcf_result *res)
35{
36 const struct nf_conntrack_tuple_hash *thash;
37 struct nf_conntrack_tuple tuple;
38 enum ip_conntrack_info ctinfo;
39 struct tcf_connmark_info *ca = a->priv;
40 struct nf_conn *c;
41 int proto;
42
43 spin_lock(&ca->tcf_lock);
44 ca->tcf_tm.lastuse = jiffies;
45 bstats_update(&ca->tcf_bstats, skb);
46
47 if (skb->protocol == htons(ETH_P_IP)) {
48 if (skb->len < sizeof(struct iphdr))
49 goto out;
50
51 proto = NFPROTO_IPV4;
52 } else if (skb->protocol == htons(ETH_P_IPV6)) {
53 if (skb->len < sizeof(struct ipv6hdr))
54 goto out;
55
56 proto = NFPROTO_IPV6;
57 } else {
58 goto out;
59 }
60
61 c = nf_ct_get(skb, &ctinfo);
62 if (c) {
63 skb->mark = c->mark;
64
65 ca->tcf_qstats.overlimits++;
66 goto out;
67 }
68
69 if (!nf_ct_get_tuplepr(skb, skb_network_offset(skb),
70 proto, &tuple))
71 goto out;
72
73 thash = nf_conntrack_find_get(dev_net(skb->dev), ca->zone, &tuple);
74 if (!thash)
75 goto out;
76
77 c = nf_ct_tuplehash_to_ctrack(thash);
78
79 ca->tcf_qstats.overlimits++;
80 skb->mark = c->mark;
81 nf_ct_put(c);
82
83out:
84 spin_unlock(&ca->tcf_lock);
85 return ca->tcf_action;
86}
87
88static const struct nla_policy connmark_policy[TCA_CONNMARK_MAX + 1] = {
89 [TCA_CONNMARK_PARMS] = { .len = sizeof(struct tc_connmark) },
90};
91
92static int tcf_connmark_init(struct net *net, struct nlattr *nla,
93 struct nlattr *est, struct tc_action *a,
94 int ovr, int bind)
95{
96 struct nlattr *tb[TCA_CONNMARK_MAX + 1];
97 struct tcf_connmark_info *ci;
98 struct tc_connmark *parm;
99 int ret = 0;
100
101 if (!nla)
102 return -EINVAL;
103
104 ret = nla_parse_nested(tb, TCA_CONNMARK_MAX, nla, connmark_policy);
105 if (ret < 0)
106 return ret;
107
108 parm = nla_data(tb[TCA_CONNMARK_PARMS]);
109
110 if (!tcf_hash_check(parm->index, a, bind)) {
111 ret = tcf_hash_create(parm->index, est, a, sizeof(*ci), bind);
112 if (ret)
113 return ret;
114
115 ci = to_connmark(a);
116 ci->tcf_action = parm->action;
117 ci->zone = parm->zone;
118
119 tcf_hash_insert(a);
120 ret = ACT_P_CREATED;
121 } else {
122 ci = to_connmark(a);
123 if (bind)
124 return 0;
125 tcf_hash_release(a, bind);
126 if (!ovr)
127 return -EEXIST;
128
129 ci->tcf_action = parm->action;
130 ci->zone = parm->zone;
131 }
132
133 return ret;
134}
135
136static inline int tcf_connmark_dump(struct sk_buff *skb, struct tc_action *a,
137 int bind, int ref)
138{
139 unsigned char *b = skb_tail_pointer(skb);
140 struct tcf_connmark_info *ci = a->priv;
141
142 struct tc_connmark opt = {
143 .index = ci->tcf_index,
144 .refcnt = ci->tcf_refcnt - ref,
145 .bindcnt = ci->tcf_bindcnt - bind,
146 .action = ci->tcf_action,
147 .zone = ci->zone,
148 };
149 struct tcf_t t;
150
151 if (nla_put(skb, TCA_CONNMARK_PARMS, sizeof(opt), &opt))
152 goto nla_put_failure;
153
154 t.install = jiffies_to_clock_t(jiffies - ci->tcf_tm.install);
155 t.lastuse = jiffies_to_clock_t(jiffies - ci->tcf_tm.lastuse);
156 t.expires = jiffies_to_clock_t(ci->tcf_tm.expires);
157 if (nla_put(skb, TCA_CONNMARK_TM, sizeof(t), &t))
158 goto nla_put_failure;
159
160 return skb->len;
161nla_put_failure:
162 nlmsg_trim(skb, b);
163 return -1;
164}
165
166static struct tc_action_ops act_connmark_ops = {
167 .kind = "connmark",
168 .type = TCA_ACT_CONNMARK,
169 .owner = THIS_MODULE,
170 .act = tcf_connmark,
171 .dump = tcf_connmark_dump,
172 .init = tcf_connmark_init,
173};
174
175static int __init connmark_init_module(void)
176{
177 return tcf_register_action(&act_connmark_ops, CONNMARK_TAB_MASK);
178}
179
180static void __exit connmark_cleanup_module(void)
181{
182 tcf_unregister_action(&act_connmark_ops);
183}
184
185module_init(connmark_init_module);
186module_exit(connmark_cleanup_module);
187MODULE_AUTHOR("Felix Fietkau <nbd@openwrt.org>");
188MODULE_DESCRIPTION("Connection tracking mark restoring");
189MODULE_LICENSE("GPL");
190
191
