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12#include <linux/module.h>
13#include <linux/init.h>
14#include <linux/list.h>
15#include <linux/skbuff.h>
16#include <linux/netlink.h>
17#include <linux/netfilter.h>
18#include <linux/netfilter_ipv6.h>
19#include <linux/netfilter/nfnetlink.h>
20#include <linux/netfilter/nf_tables.h>
21#include <net/netfilter/nf_tables.h>
22#include <net/netfilter/nf_tables_ipv6.h>
23#include <net/route.h>
24
25static unsigned int nf_route_table_hook(const struct nf_hook_ops *ops,
26 struct sk_buff *skb,
27 const struct nf_hook_state *state)
28{
29 unsigned int ret;
30 struct nft_pktinfo pkt;
31 struct in6_addr saddr, daddr;
32 u_int8_t hop_limit;
33 u32 mark, flowlabel;
34
35
36 if (nft_set_pktinfo_ipv6(&pkt, ops, skb, state) < 0)
37 return NF_DROP;
38
39
40 memcpy(&saddr, &ipv6_hdr(skb)->saddr, sizeof(saddr));
41 memcpy(&daddr, &ipv6_hdr(skb)->daddr, sizeof(daddr));
42 mark = skb->mark;
43 hop_limit = ipv6_hdr(skb)->hop_limit;
44
45
46 flowlabel = *((u32 *)ipv6_hdr(skb));
47
48 ret = nft_do_chain(&pkt, ops);
49 if (ret != NF_DROP && ret != NF_QUEUE &&
50 (memcmp(&ipv6_hdr(skb)->saddr, &saddr, sizeof(saddr)) ||
51 memcmp(&ipv6_hdr(skb)->daddr, &daddr, sizeof(daddr)) ||
52 skb->mark != mark ||
53 ipv6_hdr(skb)->hop_limit != hop_limit ||
54 flowlabel != *((u_int32_t *)ipv6_hdr(skb))))
55 return ip6_route_me_harder(skb) == 0 ? ret : NF_DROP;
56
57 return ret;
58}
59
60static const struct nf_chain_type nft_chain_route_ipv6 = {
61 .name = "route",
62 .type = NFT_CHAIN_T_ROUTE,
63 .family = NFPROTO_IPV6,
64 .owner = THIS_MODULE,
65 .hook_mask = (1 << NF_INET_LOCAL_OUT),
66 .hooks = {
67 [NF_INET_LOCAL_OUT] = nf_route_table_hook,
68 },
69};
70
71static int __init nft_chain_route_init(void)
72{
73 return nft_register_chain_type(&nft_chain_route_ipv6);
74}
75
76static void __exit nft_chain_route_exit(void)
77{
78 nft_unregister_chain_type(&nft_chain_route_ipv6);
79}
80
81module_init(nft_chain_route_init);
82module_exit(nft_chain_route_exit);
83
84MODULE_LICENSE("GPL");
85MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
86MODULE_ALIAS_NFT_CHAIN(AF_INET6, "route");
87