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1/*
2 * xfrm6_output.c - Common IPsec encapsulation code for IPv6.
3 * Copyright (C) 2002 USAGI/WIDE Project
4 * Copyright (c) 2004 Herbert Xu <herbert@gondor.apana.org.au>
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 */
11
12#include <linux/if_ether.h>
13#include <linux/kernel.h>
14#include <linux/module.h>
15#include <linux/skbuff.h>
16#include <linux/icmpv6.h>
17#include <linux/netfilter_ipv6.h>
18#include <net/dst.h>
19#include <net/ipv6.h>
20#include <net/ip6_route.h>
21#include <net/xfrm.h>
22
23int xfrm6_find_1stfragopt(struct xfrm_state *x, struct sk_buff *skb,
24 u8 **prevhdr)
25{
26 return ip6_find_1stfragopt(skb, prevhdr);
27}
28
29EXPORT_SYMBOL(xfrm6_find_1stfragopt);
30
31static int xfrm6_tunnel_check_size(struct sk_buff *skb)
32{
33 int mtu, ret = 0;
34 struct dst_entry *dst = skb_dst(skb);
35
36 mtu = dst_mtu(dst);
37 if (mtu < IPV6_MIN_MTU)
38 mtu = IPV6_MIN_MTU;
39
40 if (!skb->local_df && skb->len > mtu) {
41 skb->dev = dst->dev;
42 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
43 ret = -EMSGSIZE;
44 }
45
46 return ret;
47}
48
49int xfrm6_extract_output(struct xfrm_state *x, struct sk_buff *skb)
50{
51 int err;
52
53 err = xfrm6_tunnel_check_size(skb);
54 if (err)
55 return err;
56
57 XFRM_MODE_SKB_CB(skb)->protocol = ipv6_hdr(skb)->nexthdr;
58
59 return xfrm6_extract_header(skb);
60}
61
62int xfrm6_prepare_output(struct xfrm_state *x, struct sk_buff *skb)
63{
64 int err;
65
66 err = xfrm_inner_extract_output(x, skb);
67 if (err)
68 return err;
69
70 memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
71#ifdef CONFIG_NETFILTER
72 IP6CB(skb)->flags |= IP6SKB_XFRM_TRANSFORMED;
73#endif
74
75 skb->protocol = htons(ETH_P_IPV6);
76 skb->local_df = 1;
77
78 return x->outer_mode->output2(x, skb);
79}
80EXPORT_SYMBOL(xfrm6_prepare_output);
81
82int xfrm6_output_finish(struct sk_buff *skb)
83{
84#ifdef CONFIG_NETFILTER
85 IP6CB(skb)->flags |= IP6SKB_XFRM_TRANSFORMED;
86#endif
87
88 skb->protocol = htons(ETH_P_IPV6);
89 return xfrm_output(skb);
90}
91
92static int __xfrm6_output(struct sk_buff *skb)
93{
94 struct dst_entry *dst = skb_dst(skb);
95 struct xfrm_state *x = dst->xfrm;
96
97 if ((x && x->props.mode == XFRM_MODE_TUNNEL) &&
98 ((skb->len > ip6_skb_dst_mtu(skb) && !skb_is_gso(skb)) ||
99 dst_allfrag(skb_dst(skb)))) {
100 return ip6_fragment(skb, x->outer_mode->afinfo->output_finish);
101 }
102 return x->outer_mode->afinfo->output_finish(skb);
103}
104
105int xfrm6_output(struct sk_buff *skb)
106{
107 return NF_HOOK(NFPROTO_IPV6, NF_INET_POST_ROUTING, skb, NULL,
108 skb_dst(skb)->dev, __xfrm6_output);
109}
1/*
2 * xfrm6_output.c - Common IPsec encapsulation code for IPv6.
3 * Copyright (C) 2002 USAGI/WIDE Project
4 * Copyright (c) 2004 Herbert Xu <herbert@gondor.apana.org.au>
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 */
11
12#include <linux/if_ether.h>
13#include <linux/kernel.h>
14#include <linux/module.h>
15#include <linux/skbuff.h>
16#include <linux/icmpv6.h>
17#include <linux/netfilter_ipv6.h>
18#include <net/dst.h>
19#include <net/ipv6.h>
20#include <net/ip6_route.h>
21#include <net/xfrm.h>
22
23int xfrm6_find_1stfragopt(struct xfrm_state *x, struct sk_buff *skb,
24 u8 **prevhdr)
25{
26 return ip6_find_1stfragopt(skb, prevhdr);
27}
28
29EXPORT_SYMBOL(xfrm6_find_1stfragopt);
30
31static int xfrm6_local_dontfrag(struct sk_buff *skb)
32{
33 int proto;
34 struct sock *sk = skb->sk;
35
36 if (sk) {
37 proto = sk->sk_protocol;
38
39 if (proto == IPPROTO_UDP || proto == IPPROTO_RAW)
40 return inet6_sk(sk)->dontfrag;
41 }
42
43 return 0;
44}
45
46static void xfrm6_local_rxpmtu(struct sk_buff *skb, u32 mtu)
47{
48 struct flowi6 fl6;
49 struct sock *sk = skb->sk;
50
51 fl6.flowi6_oif = sk->sk_bound_dev_if;
52 fl6.daddr = ipv6_hdr(skb)->daddr;
53
54 ipv6_local_rxpmtu(sk, &fl6, mtu);
55}
56
57static void xfrm6_local_error(struct sk_buff *skb, u32 mtu)
58{
59 struct flowi6 fl6;
60 struct sock *sk = skb->sk;
61
62 fl6.fl6_dport = inet_sk(sk)->inet_dport;
63 fl6.daddr = ipv6_hdr(skb)->daddr;
64
65 ipv6_local_error(sk, EMSGSIZE, &fl6, mtu);
66}
67
68static int xfrm6_tunnel_check_size(struct sk_buff *skb)
69{
70 int mtu, ret = 0;
71 struct dst_entry *dst = skb_dst(skb);
72
73 mtu = dst_mtu(dst);
74 if (mtu < IPV6_MIN_MTU)
75 mtu = IPV6_MIN_MTU;
76
77 if (!skb->local_df && skb->len > mtu) {
78 skb->dev = dst->dev;
79
80 if (xfrm6_local_dontfrag(skb))
81 xfrm6_local_rxpmtu(skb, mtu);
82 else if (skb->sk)
83 xfrm6_local_error(skb, mtu);
84 else
85 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
86 ret = -EMSGSIZE;
87 }
88
89 return ret;
90}
91
92int xfrm6_extract_output(struct xfrm_state *x, struct sk_buff *skb)
93{
94 int err;
95
96 err = xfrm6_tunnel_check_size(skb);
97 if (err)
98 return err;
99
100 XFRM_MODE_SKB_CB(skb)->protocol = ipv6_hdr(skb)->nexthdr;
101
102 return xfrm6_extract_header(skb);
103}
104
105int xfrm6_prepare_output(struct xfrm_state *x, struct sk_buff *skb)
106{
107 int err;
108
109 err = xfrm_inner_extract_output(x, skb);
110 if (err)
111 return err;
112
113 memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
114#ifdef CONFIG_NETFILTER
115 IP6CB(skb)->flags |= IP6SKB_XFRM_TRANSFORMED;
116#endif
117
118 skb->protocol = htons(ETH_P_IPV6);
119 skb->local_df = 1;
120
121 return x->outer_mode->output2(x, skb);
122}
123EXPORT_SYMBOL(xfrm6_prepare_output);
124
125int xfrm6_output_finish(struct sk_buff *skb)
126{
127#ifdef CONFIG_NETFILTER
128 IP6CB(skb)->flags |= IP6SKB_XFRM_TRANSFORMED;
129#endif
130
131 skb->protocol = htons(ETH_P_IPV6);
132 return xfrm_output(skb);
133}
134
135static int __xfrm6_output(struct sk_buff *skb)
136{
137 struct dst_entry *dst = skb_dst(skb);
138 struct xfrm_state *x = dst->xfrm;
139 int mtu = ip6_skb_dst_mtu(skb);
140
141 if (skb->len > mtu && xfrm6_local_dontfrag(skb)) {
142 xfrm6_local_rxpmtu(skb, mtu);
143 return -EMSGSIZE;
144 } else if (!skb->local_df && skb->len > mtu && skb->sk) {
145 xfrm6_local_error(skb, mtu);
146 return -EMSGSIZE;
147 }
148
149 if (x->props.mode == XFRM_MODE_TUNNEL &&
150 ((skb->len > mtu && !skb_is_gso(skb)) ||
151 dst_allfrag(skb_dst(skb)))) {
152 return ip6_fragment(skb, x->outer_mode->afinfo->output_finish);
153 }
154 return x->outer_mode->afinfo->output_finish(skb);
155}
156
157int xfrm6_output(struct sk_buff *skb)
158{
159 return NF_HOOK(NFPROTO_IPV6, NF_INET_POST_ROUTING, skb, NULL,
160 skb_dst(skb)->dev, __xfrm6_output);
161}