2 * (C) 2007 by Sebastian Claßen <sebastian.classen@freenet.ag>
3 * (C) 2007-2010 by Jan Engelhardt <jengelh@medozas.de>
5 * Extracted from xt_TEE.c
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License version 2 or later, as
9 * published by the Free Software Foundation.
11 #include <linux/module.h>
12 #include <linux/percpu.h>
13 #include <linux/skbuff.h>
14 #include <linux/netfilter.h>
16 #include <net/ip6_route.h>
17 #include <net/netfilter/ipv6/nf_dup_ipv6.h>
18 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
19 #include <net/netfilter/nf_conntrack.h>
22 static bool nf_dup_ipv6_route(struct net *net, struct sk_buff *skb,
23 const struct in6_addr *gw, int oif)
25 const struct ipv6hdr *iph = ipv6_hdr(skb);
26 struct dst_entry *dst;
29 memset(&fl6, 0, sizeof(fl6));
34 fl6.flowlabel = (__force __be32)(((iph->flow_lbl[0] & 0xF) << 16) |
35 (iph->flow_lbl[1] << 8) | iph->flow_lbl[2]);
36 fl6.flowi6_flags = FLOWI_FLAG_KNOWN_NH;
37 dst = ip6_route_output(net, NULL, &fl6);
43 skb_dst_set(skb, dst);
45 skb->protocol = htons(ETH_P_IPV6);
50 void nf_dup_ipv6(struct net *net, struct sk_buff *skb, unsigned int hooknum,
51 const struct in6_addr *gw, int oif)
53 if (this_cpu_read(nf_skb_duplicated))
55 skb = pskb_copy(skb, GFP_ATOMIC);
59 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
60 nf_conntrack_put(skb->nfct);
61 skb->nfct = &nf_ct_untracked_get()->ct_general;
62 skb->nfctinfo = IP_CT_NEW;
63 nf_conntrack_get(skb->nfct);
65 if (hooknum == NF_INET_PRE_ROUTING ||
66 hooknum == NF_INET_LOCAL_IN) {
67 struct ipv6hdr *iph = ipv6_hdr(skb);
70 if (nf_dup_ipv6_route(net, skb, gw, oif)) {
71 __this_cpu_write(nf_skb_duplicated, true);
72 ip6_local_out(net, skb->sk, skb);
73 __this_cpu_write(nf_skb_duplicated, false);
78 EXPORT_SYMBOL_GPL(nf_dup_ipv6);
80 MODULE_AUTHOR("Sebastian Claßen <sebastian.classen@freenet.ag>");
81 MODULE_AUTHOR("Jan Engelhardt <jengelh@medozas.de>");
82 MODULE_DESCRIPTION("nf_dup_ipv6: IPv6 packet duplication");
83 MODULE_LICENSE("GPL");