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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 tcf_proto *tp, 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(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(index);
41 return -ENOMEM;
42}
43
44static void em_ipset_destroy(struct tcf_proto *p, struct tcf_ematch *em)
45{
46 const struct xt_set_info *set = (const void *) em->data;
47 if (set) {
48 ip_set_nfnl_put(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 int ret, network_offset;
61
62 switch (skb->protocol) {
63 case htons(ETH_P_IP):
64 acpar.family = NFPROTO_IPV4;
65 if (!pskb_network_may_pull(skb, sizeof(struct iphdr)))
66 return 0;
67 acpar.thoff = ip_hdrlen(skb);
68 break;
69 case htons(ETH_P_IPV6):
70 acpar.family = NFPROTO_IPV6;
71 if (!pskb_network_may_pull(skb, sizeof(struct ipv6hdr)))
72 return 0;
73
74 acpar.thoff = sizeof(struct ipv6hdr);
75 break;
76 default:
77 return 0;
78 }
79
80 acpar.hooknum = 0;
81
82 opt.family = acpar.family;
83 opt.dim = set->dim;
84 opt.flags = set->flags;
85 opt.cmdflags = 0;
86 opt.ext.timeout = ~0u;
87
88 network_offset = skb_network_offset(skb);
89 skb_pull(skb, network_offset);
90
91 dev = skb->dev;
92
93 rcu_read_lock();
94
95 if (dev && skb->skb_iif)
96 indev = dev_get_by_index_rcu(dev_net(dev), skb->skb_iif);
97
98 acpar.in = indev ? indev : dev;
99 acpar.out = dev;
100
101 ret = ip_set_test(set->index, skb, &acpar, &opt);
102
103 rcu_read_unlock();
104
105 skb_push(skb, network_offset);
106 return ret;
107}
108
109static struct tcf_ematch_ops em_ipset_ops = {
110 .kind = TCF_EM_IPSET,
111 .change = em_ipset_change,
112 .destroy = em_ipset_destroy,
113 .match = em_ipset_match,
114 .owner = THIS_MODULE,
115 .link = LIST_HEAD_INIT(em_ipset_ops.link)
116};
117
118static int __init init_em_ipset(void)
119{
120 return tcf_em_register(&em_ipset_ops);
121}
122
123static void __exit exit_em_ipset(void)
124{
125 tcf_em_unregister(&em_ipset_ops);
126}
127
128MODULE_LICENSE("GPL");
129MODULE_AUTHOR("Florian Westphal <fw@strlen.de>");
130MODULE_DESCRIPTION("TC extended match for IP sets");
131
132module_init(init_em_ipset);
133module_exit(exit_em_ipset);
134
135MODULE_ALIAS_TCF_EMATCH(TCF_EM_IPSET);
136