1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
|
/*
* xfrm6_output.c - Common IPsec encapsulation code for IPv6.
* Copyright (C) 2002 USAGI/WIDE Project
* Copyright (c) 2004 Herbert Xu <herbert@gondor.apana.org.au>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/if_ether.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/icmpv6.h>
#include <linux/netfilter_ipv6.h>
#include <net/dst.h>
#include <net/ipv6.h>
#include <net/ip6_route.h>
#include <net/xfrm.h>
int xfrm6_find_1stfragopt(struct xfrm_state *x, struct sk_buff *skb,
u8 **prevhdr)
{
return ip6_find_1stfragopt(skb, prevhdr);
}
EXPORT_SYMBOL(xfrm6_find_1stfragopt);
static int xfrm6_local_dontfrag(struct sk_buff *skb)
{
int proto;
struct sock *sk = skb->sk;
if (sk) {
if (sk->sk_family != AF_INET6)
return 0;
proto = sk->sk_protocol;
if (proto == IPPROTO_UDP || proto == IPPROTO_RAW)
return inet6_sk(sk)->dontfrag;
}
return 0;
}
static void xfrm6_local_rxpmtu(struct sk_buff *skb, u32 mtu)
{
struct flowi6 fl6;
struct sock *sk = skb->sk;
fl6.flowi6_oif = sk->sk_bound_dev_if;
fl6.daddr = ipv6_hdr(skb)->daddr;
ipv6_local_rxpmtu(sk, &fl6, mtu);
}
void xfrm6_local_error(struct sk_buff *skb, u32 mtu)
{
struct flowi6 fl6;
struct sock *sk = skb->sk;
fl6.fl6_dport = inet_sk(sk)->inet_dport;
fl6.daddr = ipv6_hdr(skb)->daddr;
ipv6_local_error(sk, EMSGSIZE, &fl6, mtu);
}
static int xfrm6_tunnel_check_size(struct sk_buff *skb)
{
int mtu, ret = 0;
struct dst_entry *dst = skb_dst(skb);
mtu = dst_mtu(dst);
if (mtu < IPV6_MIN_MTU)
mtu = IPV6_MIN_MTU;
if (!skb->local_df && skb->len > mtu) {
skb->dev = dst->dev;
if (xfrm6_local_dontfrag(skb))
xfrm6_local_rxpmtu(skb, mtu);
else if (skb->sk)
xfrm_local_error(skb, mtu);
else
icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
ret = -EMSGSIZE;
}
return ret;
}
int xfrm6_extract_output(struct xfrm_state *x, struct sk_buff *skb)
{
int err;
err = xfrm6_tunnel_check_size(skb);
if (err)
return err;
XFRM_MODE_SKB_CB(skb)->protocol = ipv6_hdr(skb)->nexthdr;
return xfrm6_extract_header(skb);
}
int xfrm6_prepare_output(struct xfrm_state *x, struct sk_buff *skb)
{
int err;
err = xfrm_inner_extract_output(x, skb);
if (err)
return err;
memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
#ifdef CONFIG_NETFILTER
IP6CB(skb)->flags |= IP6SKB_XFRM_TRANSFORMED;
#endif
skb->protocol = htons(ETH_P_IPV6);
skb->local_df = 1;
return x->outer_mode->output2(x, skb);
}
EXPORT_SYMBOL(xfrm6_prepare_output);
int xfrm6_output_finish(struct sk_buff *skb)
{
#ifdef CONFIG_NETFILTER
IP6CB(skb)->flags |= IP6SKB_XFRM_TRANSFORMED;
#endif
skb->protocol = htons(ETH_P_IPV6);
return xfrm_output(skb);
}
static int __xfrm6_output(struct sk_buff *skb)
{
struct dst_entry *dst = skb_dst(skb);
struct xfrm_state *x = dst->xfrm;
int mtu = xfrm_skb_dst_mtu(skb);
if (mtu < IPV6_MIN_MTU)
mtu = IPV6_MIN_MTU;
if (skb->len > mtu && xfrm6_local_dontfrag(skb)) {
xfrm6_local_rxpmtu(skb, mtu);
return -EMSGSIZE;
} else if (!skb->local_df && skb->len > mtu && skb->sk) {
xfrm_local_error(skb, mtu);
return -EMSGSIZE;
}
if (x->props.mode == XFRM_MODE_TUNNEL &&
((skb->len > mtu && !skb_is_gso(skb)) ||
dst_allfrag(skb_dst(skb)))) {
return ip6_fragment(skb, x->outer_mode->afinfo->output_finish);
}
return x->outer_mode->afinfo->output_finish(skb);
}
int xfrm6_output(struct sk_buff *skb)
{
return NF_HOOK(NFPROTO_IPV6, NF_INET_POST_ROUTING, skb, NULL,
skb_dst(skb)->dev, __xfrm6_output);
}
|
