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11#include <linux/gfp.h>
12#include <linux/module.h>
13#include <linux/types.h>
14#include <linux/kernel.h>
15#include <linux/string.h>
16#include <linux/skbuff.h>
17#include <linux/netfilter/xt_set.h>
18#include <linux/ipv6.h>
19#include <net/ip.h>
20#include <net/pkt_cls.h>
21
22static int em_ipset_change(struct net *net, void *data, int data_len,
23 struct tcf_ematch *em)
24{
25 struct xt_set_info *set = data;
26 ip_set_id_t index;
27
28 if (data_len != sizeof(*set))
29 return -EINVAL;
30
31 index = ip_set_nfnl_get_byindex(net, set->index);
32 if (index == IPSET_INVALID_ID)
33 return -ENOENT;
34
35 em->datalen = sizeof(*set);
36 em->data = (unsigned long)kmemdup(data, em->datalen, GFP_KERNEL);
37 if (em->data)
38 return 0;
39
40 ip_set_nfnl_put(net, index);
41 return -ENOMEM;
42}
43
44static void em_ipset_destroy(struct tcf_ematch *em)
45{
46 const struct xt_set_info *set = (const void *) em->data;
47 if (set) {
48 ip_set_nfnl_put(em->net, set->index);
49 kfree((void *) em->data);
50 }
51}
52
53static int em_ipset_match(struct sk_buff *skb, struct tcf_ematch *em,
54 struct tcf_pkt_info *info)
55{
56 struct ip_set_adt_opt opt;
57 struct xt_action_param acpar;
58 const struct xt_set_info *set = (const void *) em->data;
59 struct net_device *dev, *indev = NULL;
60 struct nf_hook_state state = {
61 .net = em->net,
62 };
63 int ret, network_offset;
64
65 switch (tc_skb_protocol(skb)) {
66 case htons(ETH_P_IP):
67 state.pf = NFPROTO_IPV4;
68 if (!pskb_network_may_pull(skb, sizeof(struct iphdr)))
69 return 0;
70 acpar.thoff = ip_hdrlen(skb);
71 break;
72 case htons(ETH_P_IPV6):
73 state.pf = NFPROTO_IPV6;
74 if (!pskb_network_may_pull(skb, sizeof(struct ipv6hdr)))
75 return 0;
76
77 acpar.thoff = sizeof(struct ipv6hdr);
78 break;
79 default:
80 return 0;
81 }
82
83 opt.family = state.pf;
84 opt.dim = set->dim;
85 opt.flags = set->flags;
86 opt.cmdflags = 0;
87 opt.ext.timeout = ~0u;
88
89 network_offset = skb_network_offset(skb);
90 skb_pull(skb, network_offset);
91
92 dev = skb->dev;
93
94 rcu_read_lock();
95
96 if (skb->skb_iif)
97 indev = dev_get_by_index_rcu(em->net, skb->skb_iif);
98
99 state.in = indev ? indev : dev;
100 state.out = dev;
101 acpar.state = &state;
102
103 ret = ip_set_test(set->index, skb, &acpar, &opt);
104
105 rcu_read_unlock();
106
107 skb_push(skb, network_offset);
108 return ret;
109}
110
111static struct tcf_ematch_ops em_ipset_ops = {
112 .kind = TCF_EM_IPSET,
113 .change = em_ipset_change,
114 .destroy = em_ipset_destroy,
115 .match = em_ipset_match,
116 .owner = THIS_MODULE,
117 .link = LIST_HEAD_INIT(em_ipset_ops.link)
118};
119
120static int __init init_em_ipset(void)
121{
122 return tcf_em_register(&em_ipset_ops);
123}
124
125static void __exit exit_em_ipset(void)
126{
127 tcf_em_unregister(&em_ipset_ops);
128}
129
130MODULE_LICENSE("GPL");
131MODULE_AUTHOR("Florian Westphal <fw@strlen.de>");
132MODULE_DESCRIPTION("TC extended match for IP sets");
133
134module_init(init_em_ipset);
135module_exit(exit_em_ipset);
136
137MODULE_ALIAS_TCF_EMATCH(TCF_EM_IPSET);
138
