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
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
|
/*
* IP Payload Compression Protocol (IPComp) for IPv6 - RFC3173
*
* Copyright (C)2003 USAGI/WIDE Project
*
* Author Mitsuru KANDA <mk@linux-ipv6.org>
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/*
* [Memo]
*
* Outbound:
* The compression of IP datagram MUST be done before AH/ESP processing,
* fragmentation, and the addition of Hop-by-Hop/Routing header.
*
* Inbound:
* The decompression of IP datagram MUST be done after the reassembly,
* AH/ESP processing.
*/
#define pr_fmt(fmt) "IPv6: " fmt
#include <linux/module.h>
#include <net/ip.h>
#include <net/xfrm.h>
#include <net/ipcomp.h>
#include <linux/crypto.h>
#include <linux/err.h>
#include <linux/pfkeyv2.h>
#include <linux/random.h>
#include <linux/percpu.h>
#include <linux/smp.h>
#include <linux/list.h>
#include <linux/vmalloc.h>
#include <linux/rtnetlink.h>
#include <net/ip6_route.h>
#include <net/icmp.h>
#include <net/ipv6.h>
#include <net/protocol.h>
#include <linux/ipv6.h>
#include <linux/icmpv6.h>
#include <linux/mutex.h>
static void ipcomp6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
u8 type, u8 code, int offset, __be32 info)
{
struct net *net = dev_net(skb->dev);
__be32 spi;
const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data;
struct ip_comp_hdr *ipcomph =
(struct ip_comp_hdr *)(skb->data + offset);
struct xfrm_state *x;
if (type != ICMPV6_PKT_TOOBIG &&
type != NDISC_REDIRECT)
return;
spi = htonl(ntohs(ipcomph->cpi));
x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr,
spi, IPPROTO_COMP, AF_INET6);
if (!x)
return;
if (type == NDISC_REDIRECT)
ip6_redirect(skb, net, skb->dev->ifindex, 0);
else
ip6_update_pmtu(skb, net, info, 0, 0);
xfrm_state_put(x);
}
static struct xfrm_state *ipcomp6_tunnel_create(struct xfrm_state *x)
{
struct net *net = xs_net(x);
struct xfrm_state *t = NULL;
t = xfrm_state_alloc(net);
if (!t)
goto out;
t->id.proto = IPPROTO_IPV6;
t->id.spi = xfrm6_tunnel_alloc_spi(net, (xfrm_address_t *)&x->props.saddr);
if (!t->id.spi)
goto error;
memcpy(t->id.daddr.a6, x->id.daddr.a6, sizeof(struct in6_addr));
memcpy(&t->sel, &x->sel, sizeof(t->sel));
t->props.family = AF_INET6;
t->props.mode = x->props.mode;
memcpy(t->props.saddr.a6, x->props.saddr.a6, sizeof(struct in6_addr));
memcpy(&t->mark, &x->mark, sizeof(t->mark));
if (xfrm_init_state(t))
goto error;
atomic_set(&t->tunnel_users, 1);
out:
return t;
error:
t->km.state = XFRM_STATE_DEAD;
xfrm_state_put(t);
t = NULL;
goto out;
}
static int ipcomp6_tunnel_attach(struct xfrm_state *x)
{
struct net *net = xs_net(x);
int err = 0;
struct xfrm_state *t = NULL;
__be32 spi;
u32 mark = x->mark.m & x->mark.v;
spi = xfrm6_tunnel_spi_lookup(net, (xfrm_address_t *)&x->props.saddr);
if (spi)
t = xfrm_state_lookup(net, mark, (xfrm_address_t *)&x->id.daddr,
spi, IPPROTO_IPV6, AF_INET6);
if (!t) {
t = ipcomp6_tunnel_create(x);
if (!t) {
err = -EINVAL;
goto out;
}
xfrm_state_insert(t);
xfrm_state_hold(t);
}
x->tunnel = t;
atomic_inc(&t->tunnel_users);
out:
return err;
}
static int ipcomp6_init_state(struct xfrm_state *x)
{
int err = -EINVAL;
x->props.header_len = 0;
switch (x->props.mode) {
case XFRM_MODE_TRANSPORT:
break;
case XFRM_MODE_TUNNEL:
x->props.header_len += sizeof(struct ipv6hdr);
break;
default:
goto out;
}
err = ipcomp_init_state(x);
if (err)
goto out;
if (x->props.mode == XFRM_MODE_TUNNEL) {
err = ipcomp6_tunnel_attach(x);
if (err)
goto out;
}
err = 0;
out:
return err;
}
static const struct xfrm_type ipcomp6_type =
{
.description = "IPCOMP6",
.owner = THIS_MODULE,
.proto = IPPROTO_COMP,
.init_state = ipcomp6_init_state,
.destructor = ipcomp_destroy,
.input = ipcomp_input,
.output = ipcomp_output,
.hdr_offset = xfrm6_find_1stfragopt,
};
static const struct inet6_protocol ipcomp6_protocol =
{
.handler = xfrm6_rcv,
.err_handler = ipcomp6_err,
.flags = INET6_PROTO_NOPOLICY,
};
static int __init ipcomp6_init(void)
{
if (xfrm_register_type(&ipcomp6_type, AF_INET6) < 0) {
pr_info("%s: can't add xfrm type\n", __func__);
return -EAGAIN;
}
if (inet6_add_protocol(&ipcomp6_protocol, IPPROTO_COMP) < 0) {
pr_info("%s: can't add protocol\n", __func__);
xfrm_unregister_type(&ipcomp6_type, AF_INET6);
return -EAGAIN;
}
return 0;
}
static void __exit ipcomp6_fini(void)
{
if (inet6_del_protocol(&ipcomp6_protocol, IPPROTO_COMP) < 0)
pr_info("%s: can't remove protocol\n", __func__);
if (xfrm_unregister_type(&ipcomp6_type, AF_INET6) < 0)
pr_info("%s: can't remove xfrm type\n", __func__);
}
module_init(ipcomp6_init);
module_exit(ipcomp6_fini);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("IP Payload Compression Protocol (IPComp) for IPv6 - RFC3173");
MODULE_AUTHOR("Mitsuru KANDA <mk@linux-ipv6.org>");
MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_COMP);
|
