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
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
|
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C)2003,2004 USAGI/WIDE Project
*
* Authors Mitsuru KANDA <mk@linux-ipv6.org>
* YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
*/
#define pr_fmt(fmt) "IPv6: " fmt
#include <linux/icmpv6.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/slab.h>
#include <net/ipv6.h>
#include <net/protocol.h>
#include <net/xfrm.h>
static struct xfrm6_tunnel __rcu *tunnel6_handlers __read_mostly;
static struct xfrm6_tunnel __rcu *tunnel46_handlers __read_mostly;
static struct xfrm6_tunnel __rcu *tunnelmpls6_handlers __read_mostly;
static DEFINE_MUTEX(tunnel6_mutex);
static inline int xfrm6_tunnel_mpls_supported(void)
{
return IS_ENABLED(CONFIG_MPLS);
}
int xfrm6_tunnel_register(struct xfrm6_tunnel *handler, unsigned short family)
{
struct xfrm6_tunnel __rcu **pprev;
struct xfrm6_tunnel *t;
int ret = -EEXIST;
int priority = handler->priority;
mutex_lock(&tunnel6_mutex);
switch (family) {
case AF_INET6:
pprev = &tunnel6_handlers;
break;
case AF_INET:
pprev = &tunnel46_handlers;
break;
case AF_MPLS:
pprev = &tunnelmpls6_handlers;
break;
default:
goto err;
}
for (; (t = rcu_dereference_protected(*pprev,
lockdep_is_held(&tunnel6_mutex))) != NULL;
pprev = &t->next) {
if (t->priority > priority)
break;
if (t->priority == priority)
goto err;
}
handler->next = *pprev;
rcu_assign_pointer(*pprev, handler);
ret = 0;
err:
mutex_unlock(&tunnel6_mutex);
return ret;
}
EXPORT_SYMBOL(xfrm6_tunnel_register);
int xfrm6_tunnel_deregister(struct xfrm6_tunnel *handler, unsigned short family)
{
struct xfrm6_tunnel __rcu **pprev;
struct xfrm6_tunnel *t;
int ret = -ENOENT;
mutex_lock(&tunnel6_mutex);
switch (family) {
case AF_INET6:
pprev = &tunnel6_handlers;
break;
case AF_INET:
pprev = &tunnel46_handlers;
break;
case AF_MPLS:
pprev = &tunnelmpls6_handlers;
break;
default:
goto err;
}
for (; (t = rcu_dereference_protected(*pprev,
lockdep_is_held(&tunnel6_mutex))) != NULL;
pprev = &t->next) {
if (t == handler) {
*pprev = handler->next;
ret = 0;
break;
}
}
err:
mutex_unlock(&tunnel6_mutex);
synchronize_net();
return ret;
}
EXPORT_SYMBOL(xfrm6_tunnel_deregister);
#define for_each_tunnel_rcu(head, handler) \
for (handler = rcu_dereference(head); \
handler != NULL; \
handler = rcu_dereference(handler->next)) \
static int tunnelmpls6_rcv(struct sk_buff *skb)
{
struct xfrm6_tunnel *handler;
if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
goto drop;
for_each_tunnel_rcu(tunnelmpls6_handlers, handler)
if (!handler->handler(skb))
return 0;
icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
drop:
kfree_skb(skb);
return 0;
}
static int tunnel6_rcv(struct sk_buff *skb)
{
struct xfrm6_tunnel *handler;
if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
goto drop;
for_each_tunnel_rcu(tunnel6_handlers, handler)
if (!handler->handler(skb))
return 0;
icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
drop:
kfree_skb(skb);
return 0;
}
#if IS_ENABLED(CONFIG_INET6_XFRM_TUNNEL)
static int tunnel6_rcv_cb(struct sk_buff *skb, u8 proto, int err)
{
struct xfrm6_tunnel __rcu *head;
struct xfrm6_tunnel *handler;
int ret;
head = (proto == IPPROTO_IPV6) ? tunnel6_handlers : tunnel46_handlers;
for_each_tunnel_rcu(head, handler) {
if (handler->cb_handler) {
ret = handler->cb_handler(skb, err);
if (ret <= 0)
return ret;
}
}
return 0;
}
static const struct xfrm_input_afinfo tunnel6_input_afinfo = {
.family = AF_INET6,
.is_ipip = true,
.callback = tunnel6_rcv_cb,
};
#endif
static int tunnel46_rcv(struct sk_buff *skb)
{
struct xfrm6_tunnel *handler;
if (!pskb_may_pull(skb, sizeof(struct iphdr)))
goto drop;
for_each_tunnel_rcu(tunnel46_handlers, handler)
if (!handler->handler(skb))
return 0;
icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
drop:
kfree_skb(skb);
return 0;
}
static int tunnel6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
u8 type, u8 code, int offset, __be32 info)
{
struct xfrm6_tunnel *handler;
for_each_tunnel_rcu(tunnel6_handlers, handler)
if (!handler->err_handler(skb, opt, type, code, offset, info))
return 0;
return -ENOENT;
}
static int tunnel46_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
u8 type, u8 code, int offset, __be32 info)
{
struct xfrm6_tunnel *handler;
for_each_tunnel_rcu(tunnel46_handlers, handler)
if (!handler->err_handler(skb, opt, type, code, offset, info))
return 0;
return -ENOENT;
}
static int tunnelmpls6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
u8 type, u8 code, int offset, __be32 info)
{
struct xfrm6_tunnel *handler;
for_each_tunnel_rcu(tunnelmpls6_handlers, handler)
if (!handler->err_handler(skb, opt, type, code, offset, info))
return 0;
return -ENOENT;
}
static const struct inet6_protocol tunnel6_protocol = {
.handler = tunnel6_rcv,
.err_handler = tunnel6_err,
.flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
};
static const struct inet6_protocol tunnel46_protocol = {
.handler = tunnel46_rcv,
.err_handler = tunnel46_err,
.flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
};
static const struct inet6_protocol tunnelmpls6_protocol = {
.handler = tunnelmpls6_rcv,
.err_handler = tunnelmpls6_err,
.flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
};
static int __init tunnel6_init(void)
{
if (inet6_add_protocol(&tunnel6_protocol, IPPROTO_IPV6)) {
pr_err("%s: can't add protocol\n", __func__);
return -EAGAIN;
}
if (inet6_add_protocol(&tunnel46_protocol, IPPROTO_IPIP)) {
pr_err("%s: can't add protocol\n", __func__);
inet6_del_protocol(&tunnel6_protocol, IPPROTO_IPV6);
return -EAGAIN;
}
if (xfrm6_tunnel_mpls_supported() &&
inet6_add_protocol(&tunnelmpls6_protocol, IPPROTO_MPLS)) {
pr_err("%s: can't add protocol\n", __func__);
inet6_del_protocol(&tunnel6_protocol, IPPROTO_IPV6);
inet6_del_protocol(&tunnel46_protocol, IPPROTO_IPIP);
return -EAGAIN;
}
#if IS_ENABLED(CONFIG_INET6_XFRM_TUNNEL)
if (xfrm_input_register_afinfo(&tunnel6_input_afinfo)) {
pr_err("%s: can't add input afinfo\n", __func__);
inet6_del_protocol(&tunnel6_protocol, IPPROTO_IPV6);
inet6_del_protocol(&tunnel46_protocol, IPPROTO_IPIP);
if (xfrm6_tunnel_mpls_supported())
inet6_del_protocol(&tunnelmpls6_protocol, IPPROTO_MPLS);
return -EAGAIN;
}
#endif
return 0;
}
static void __exit tunnel6_fini(void)
{
#if IS_ENABLED(CONFIG_INET6_XFRM_TUNNEL)
if (xfrm_input_unregister_afinfo(&tunnel6_input_afinfo))
pr_err("%s: can't remove input afinfo\n", __func__);
#endif
if (inet6_del_protocol(&tunnel46_protocol, IPPROTO_IPIP))
pr_err("%s: can't remove protocol\n", __func__);
if (inet6_del_protocol(&tunnel6_protocol, IPPROTO_IPV6))
pr_err("%s: can't remove protocol\n", __func__);
if (xfrm6_tunnel_mpls_supported() &&
inet6_del_protocol(&tunnelmpls6_protocol, IPPROTO_MPLS))
pr_err("%s: can't remove protocol\n", __func__);
}
module_init(tunnel6_init);
module_exit(tunnel6_fini);
MODULE_DESCRIPTION("IP-in-IPv6 tunnel driver");
MODULE_LICENSE("GPL");
|
