2 * Copyright (c) 2011 Patrick Mchardy <kaber@trash.net>
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
8 * Based on Rusty Russell's IPv4 ICMP NAT code. Development of IPv6
9 * NAT funded by Astaro.
12 #include <linux/types.h>
13 #include <linux/init.h>
14 #include <linux/icmpv6.h>
16 #include <linux/netfilter.h>
17 #include <net/netfilter/nf_nat.h>
18 #include <net/netfilter/nf_nat_core.h>
19 #include <net/netfilter/nf_nat_l3proto.h>
20 #include <net/netfilter/nf_nat_l4proto.h>
23 icmpv6_in_range(const struct nf_conntrack_tuple
*tuple
,
24 enum nf_nat_manip_type maniptype
,
25 const union nf_conntrack_man_proto
*min
,
26 const union nf_conntrack_man_proto
*max
)
28 return ntohs(tuple
->src
.u
.icmp
.id
) >= ntohs(min
->icmp
.id
) &&
29 ntohs(tuple
->src
.u
.icmp
.id
) <= ntohs(max
->icmp
.id
);
33 icmpv6_unique_tuple(const struct nf_nat_l3proto
*l3proto
,
34 struct nf_conntrack_tuple
*tuple
,
35 const struct nf_nat_range
*range
,
36 enum nf_nat_manip_type maniptype
,
37 const struct nf_conn
*ct
)
40 unsigned int range_size
;
43 range_size
= ntohs(range
->max_proto
.icmp
.id
) -
44 ntohs(range
->min_proto
.icmp
.id
) + 1;
46 if (!(range
->flags
& NF_NAT_RANGE_PROTO_SPECIFIED
))
50 tuple
->src
.u
.icmp
.id
= htons(ntohs(range
->min_proto
.icmp
.id
) +
52 if (++i
== range_size
|| !nf_nat_used_tuple(tuple
, ct
))
58 icmpv6_manip_pkt(struct sk_buff
*skb
,
59 const struct nf_nat_l3proto
*l3proto
,
60 unsigned int iphdroff
, unsigned int hdroff
,
61 const struct nf_conntrack_tuple
*tuple
,
62 enum nf_nat_manip_type maniptype
)
66 if (!skb_make_writable(skb
, hdroff
+ sizeof(*hdr
)))
69 hdr
= (struct icmp6hdr
*)(skb
->data
+ hdroff
);
70 l3proto
->csum_update(skb
, iphdroff
, &hdr
->icmp6_cksum
,
72 if (hdr
->icmp6_type
== ICMPV6_ECHO_REQUEST
||
73 hdr
->icmp6_type
== ICMPV6_ECHO_REPLY
) {
74 inet_proto_csum_replace2(&hdr
->icmp6_cksum
, skb
,
75 hdr
->icmp6_identifier
,
76 tuple
->src
.u
.icmp
.id
, false);
77 hdr
->icmp6_identifier
= tuple
->src
.u
.icmp
.id
;
82 const struct nf_nat_l4proto nf_nat_l4proto_icmpv6
= {
83 .l4proto
= IPPROTO_ICMPV6
,
84 .manip_pkt
= icmpv6_manip_pkt
,
85 .in_range
= icmpv6_in_range
,
86 .unique_tuple
= icmpv6_unique_tuple
,
87 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
88 .nlattr_to_range
= nf_nat_l4proto_nlattr_to_range
,