blob: 8e472518f9f6856dcd5802c16373b6579f7284eb [file] [log] [blame]
Felix Fietkau22a5dc02015-01-18 16:35:14 -05001/*
2 * net/sched/act_connmark.c netfilter connmark retriever action
3 * skb mark is over-written
4 *
5 * Copyright (c) 2011 Felix Fietkau <nbd@openwrt.org>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11*/
12
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 /* using overlimits stats to count how many packets marked */
65 ca->tcf_qstats.overlimits++;
66 nf_ct_put(c);
67 goto out;
68 }
69
70 if (!nf_ct_get_tuplepr(skb, skb_network_offset(skb),
71 proto, &tuple))
72 goto out;
73
74 thash = nf_conntrack_find_get(dev_net(skb->dev), ca->zone, &tuple);
75 if (!thash)
76 goto out;
77
78 c = nf_ct_tuplehash_to_ctrack(thash);
79 /* using overlimits stats to count how many packets marked */
80 ca->tcf_qstats.overlimits++;
81 skb->mark = c->mark;
82 nf_ct_put(c);
83
84out:
85 skb->nfct = NULL;
86 spin_unlock(&ca->tcf_lock);
87 return ca->tcf_action;
88}
89
90static const struct nla_policy connmark_policy[TCA_CONNMARK_MAX + 1] = {
91 [TCA_CONNMARK_PARMS] = { .len = sizeof(struct tc_connmark) },
92};
93
94static int tcf_connmark_init(struct net *net, struct nlattr *nla,
95 struct nlattr *est, struct tc_action *a,
96 int ovr, int bind)
97{
98 struct nlattr *tb[TCA_CONNMARK_MAX + 1];
99 struct tcf_connmark_info *ci;
100 struct tc_connmark *parm;
101 int ret = 0;
102
103 if (!nla)
104 return -EINVAL;
105
106 ret = nla_parse_nested(tb, TCA_CONNMARK_MAX, nla, connmark_policy);
107 if (ret < 0)
108 return ret;
109
110 parm = nla_data(tb[TCA_CONNMARK_PARMS]);
111
112 if (!tcf_hash_check(parm->index, a, bind)) {
113 ret = tcf_hash_create(parm->index, est, a, sizeof(*ci), bind);
114 if (ret)
115 return ret;
116
117 ci = to_connmark(a);
118 ci->tcf_action = parm->action;
119 ci->zone = parm->zone;
120
121 tcf_hash_insert(a);
122 ret = ACT_P_CREATED;
123 } else {
124 ci = to_connmark(a);
125 if (bind)
126 return 0;
127 tcf_hash_release(a, bind);
128 if (!ovr)
129 return -EEXIST;
130 /* replacing action and zone */
131 ci->tcf_action = parm->action;
132 ci->zone = parm->zone;
133 }
134
135 return ret;
136}
137
138static inline int tcf_connmark_dump(struct sk_buff *skb, struct tc_action *a,
139 int bind, int ref)
140{
141 unsigned char *b = skb_tail_pointer(skb);
142 struct tcf_connmark_info *ci = a->priv;
143
144 struct tc_connmark opt = {
145 .index = ci->tcf_index,
146 .refcnt = ci->tcf_refcnt - ref,
147 .bindcnt = ci->tcf_bindcnt - bind,
148 .action = ci->tcf_action,
149 .zone = ci->zone,
150 };
151 struct tcf_t t;
152
153 if (nla_put(skb, TCA_CONNMARK_PARMS, sizeof(opt), &opt))
154 goto nla_put_failure;
155
156 t.install = jiffies_to_clock_t(jiffies - ci->tcf_tm.install);
157 t.lastuse = jiffies_to_clock_t(jiffies - ci->tcf_tm.lastuse);
158 t.expires = jiffies_to_clock_t(ci->tcf_tm.expires);
159 if (nla_put(skb, TCA_CONNMARK_TM, sizeof(t), &t))
160 goto nla_put_failure;
161
162 return skb->len;
163nla_put_failure:
164 nlmsg_trim(skb, b);
165 return -1;
166}
167
168static struct tc_action_ops act_connmark_ops = {
169 .kind = "connmark",
170 .type = TCA_ACT_CONNMARK,
171 .owner = THIS_MODULE,
172 .act = tcf_connmark,
173 .dump = tcf_connmark_dump,
174 .init = tcf_connmark_init,
175};
176
177static int __init connmark_init_module(void)
178{
179 return tcf_register_action(&act_connmark_ops, CONNMARK_TAB_MASK);
180}
181
182static void __exit connmark_cleanup_module(void)
183{
184 tcf_unregister_action(&act_connmark_ops);
185}
186
187module_init(connmark_init_module);
188module_exit(connmark_cleanup_module);
189MODULE_AUTHOR("Felix Fietkau <nbd@openwrt.org>");
190MODULE_DESCRIPTION("Connection tracking mark restoring");
191MODULE_LICENSE("GPL");
192