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12#include <linux/module.h>
13#include <linux/skbuff.h>
14#include <linux/socket.h>
15#include <linux/hash.h>
16#include <linux/l2tp.h>
17#include <linux/in.h>
18#include <linux/etherdevice.h>
19#include <linux/spinlock.h>
20#include <net/sock.h>
21#include <net/ip.h>
22#include <net/icmp.h>
23#include <net/udp.h>
24#include <net/inet_common.h>
25#include <net/inet_hashtables.h>
26#include <net/tcp_states.h>
27#include <net/protocol.h>
28#include <net/xfrm.h>
29#include <net/net_namespace.h>
30#include <net/netns/generic.h>
31
32#include "l2tp_core.h"
33
34
35#define L2TP_ETH_DEV_NAME "l2tpeth%d"
36
37
38struct l2tp_eth {
39 struct net_device *dev;
40 struct sock *tunnel_sock;
41 struct l2tp_session *session;
42 struct list_head list;
43};
44
45
46struct l2tp_eth_sess {
47 struct net_device *dev;
48};
49
50
51static unsigned int l2tp_eth_net_id;
52struct l2tp_eth_net {
53 struct list_head l2tp_eth_dev_list;
54 spinlock_t l2tp_eth_lock;
55};
56
57static inline struct l2tp_eth_net *l2tp_eth_pernet(struct net *net)
58{
59 return net_generic(net, l2tp_eth_net_id);
60}
61
62static int l2tp_eth_dev_init(struct net_device *dev)
63{
64 struct l2tp_eth *priv = netdev_priv(dev);
65
66 priv->dev = dev;
67 eth_hw_addr_random(dev);
68 memset(&dev->broadcast[0], 0xff, 6);
69
70 return 0;
71}
72
73static void l2tp_eth_dev_uninit(struct net_device *dev)
74{
75 struct l2tp_eth *priv = netdev_priv(dev);
76 struct l2tp_eth_net *pn = l2tp_eth_pernet(dev_net(dev));
77
78 spin_lock(&pn->l2tp_eth_lock);
79 list_del_init(&priv->list);
80 spin_unlock(&pn->l2tp_eth_lock);
81 dev_put(dev);
82}
83
84static int l2tp_eth_dev_xmit(struct sk_buff *skb, struct net_device *dev)
85{
86 struct l2tp_eth *priv = netdev_priv(dev);
87 struct l2tp_session *session = priv->session;
88
89 l2tp_xmit_skb(session, skb, session->hdr_len);
90
91 dev->stats.tx_bytes += skb->len;
92 dev->stats.tx_packets++;
93
94 return 0;
95}
96
97static struct net_device_ops l2tp_eth_netdev_ops = {
98 .ndo_init = l2tp_eth_dev_init,
99 .ndo_uninit = l2tp_eth_dev_uninit,
100 .ndo_start_xmit = l2tp_eth_dev_xmit,
101};
102
103static void l2tp_eth_dev_setup(struct net_device *dev)
104{
105 ether_setup(dev);
106 dev->priv_flags &= ~IFF_TX_SKB_SHARING;
107 dev->netdev_ops = &l2tp_eth_netdev_ops;
108 dev->destructor = free_netdev;
109}
110
111static void l2tp_eth_dev_recv(struct l2tp_session *session, struct sk_buff *skb, int data_len)
112{
113 struct l2tp_eth_sess *spriv = l2tp_session_priv(session);
114 struct net_device *dev = spriv->dev;
115
116 if (session->debug & L2TP_MSG_DATA) {
117 unsigned int length;
118 int offset;
119 u8 *ptr = skb->data;
120
121 length = min(32u, skb->len);
122 if (!pskb_may_pull(skb, length))
123 goto error;
124
125 printk(KERN_DEBUG "%s: eth recv: ", session->name);
126
127 offset = 0;
128 do {
129 printk(" %02X", ptr[offset]);
130 } while (++offset < length);
131
132 printk("\n");
133 }
134
135 if (!pskb_may_pull(skb, sizeof(ETH_HLEN)))
136 goto error;
137
138 secpath_reset(skb);
139
140
141 skb->ip_summed = CHECKSUM_NONE;
142
143 skb_dst_drop(skb);
144 nf_reset(skb);
145
146 if (dev_forward_skb(dev, skb) == NET_RX_SUCCESS) {
147 dev->stats.rx_packets++;
148 dev->stats.rx_bytes += data_len;
149 } else
150 dev->stats.rx_errors++;
151
152 return;
153
154error:
155 dev->stats.rx_errors++;
156 kfree_skb(skb);
157}
158
159static void l2tp_eth_delete(struct l2tp_session *session)
160{
161 struct l2tp_eth_sess *spriv;
162 struct net_device *dev;
163
164 if (session) {
165 spriv = l2tp_session_priv(session);
166 dev = spriv->dev;
167 if (dev) {
168 unregister_netdev(dev);
169 spriv->dev = NULL;
170 }
171 }
172}
173
174#if defined(CONFIG_L2TP_DEBUGFS) || defined(CONFIG_L2TP_DEBUGFS_MODULE)
175static void l2tp_eth_show(struct seq_file *m, void *arg)
176{
177 struct l2tp_session *session = arg;
178 struct l2tp_eth_sess *spriv = l2tp_session_priv(session);
179 struct net_device *dev = spriv->dev;
180
181 seq_printf(m, " interface %s\n", dev->name);
182}
183#endif
184
185static int l2tp_eth_create(struct net *net, u32 tunnel_id, u32 session_id, u32 peer_session_id, struct l2tp_session_cfg *cfg)
186{
187 struct net_device *dev;
188 char name[IFNAMSIZ];
189 struct l2tp_tunnel *tunnel;
190 struct l2tp_session *session;
191 struct l2tp_eth *priv;
192 struct l2tp_eth_sess *spriv;
193 int rc;
194 struct l2tp_eth_net *pn;
195
196 tunnel = l2tp_tunnel_find(net, tunnel_id);
197 if (!tunnel) {
198 rc = -ENODEV;
199 goto out;
200 }
201
202 session = l2tp_session_find(net, tunnel, session_id);
203 if (session) {
204 rc = -EEXIST;
205 goto out;
206 }
207
208 if (cfg->ifname) {
209 dev = dev_get_by_name(net, cfg->ifname);
210 if (dev) {
211 dev_put(dev);
212 rc = -EEXIST;
213 goto out;
214 }
215 strlcpy(name, cfg->ifname, IFNAMSIZ);
216 } else
217 strcpy(name, L2TP_ETH_DEV_NAME);
218
219 session = l2tp_session_create(sizeof(*spriv), tunnel, session_id,
220 peer_session_id, cfg);
221 if (!session) {
222 rc = -ENOMEM;
223 goto out;
224 }
225
226 dev = alloc_netdev(sizeof(*priv), name, l2tp_eth_dev_setup);
227 if (!dev) {
228 rc = -ENOMEM;
229 goto out_del_session;
230 }
231
232 dev_net_set(dev, net);
233 if (session->mtu == 0)
234 session->mtu = dev->mtu - session->hdr_len;
235 dev->mtu = session->mtu;
236 dev->needed_headroom += session->hdr_len;
237
238 priv = netdev_priv(dev);
239 priv->dev = dev;
240 priv->session = session;
241 INIT_LIST_HEAD(&priv->list);
242
243 priv->tunnel_sock = tunnel->sock;
244 session->recv_skb = l2tp_eth_dev_recv;
245 session->session_close = l2tp_eth_delete;
246#if defined(CONFIG_L2TP_DEBUGFS) || defined(CONFIG_L2TP_DEBUGFS_MODULE)
247 session->show = l2tp_eth_show;
248#endif
249
250 spriv = l2tp_session_priv(session);
251 spriv->dev = dev;
252
253 rc = register_netdev(dev);
254 if (rc < 0)
255 goto out_del_dev;
256
257
258 strlcpy(session->ifname, dev->name, IFNAMSIZ);
259
260 dev_hold(dev);
261 pn = l2tp_eth_pernet(dev_net(dev));
262 spin_lock(&pn->l2tp_eth_lock);
263 list_add(&priv->list, &pn->l2tp_eth_dev_list);
264 spin_unlock(&pn->l2tp_eth_lock);
265
266 return 0;
267
268out_del_dev:
269 free_netdev(dev);
270out_del_session:
271 l2tp_session_delete(session);
272out:
273 return rc;
274}
275
276static __net_init int l2tp_eth_init_net(struct net *net)
277{
278 struct l2tp_eth_net *pn = net_generic(net, l2tp_eth_net_id);
279
280 INIT_LIST_HEAD(&pn->l2tp_eth_dev_list);
281 spin_lock_init(&pn->l2tp_eth_lock);
282
283 return 0;
284}
285
286static struct pernet_operations l2tp_eth_net_ops = {
287 .init = l2tp_eth_init_net,
288 .id = &l2tp_eth_net_id,
289 .size = sizeof(struct l2tp_eth_net),
290};
291
292
293static const struct l2tp_nl_cmd_ops l2tp_eth_nl_cmd_ops = {
294 .session_create = l2tp_eth_create,
295 .session_delete = l2tp_session_delete,
296};
297
298
299static int __init l2tp_eth_init(void)
300{
301 int err = 0;
302
303 err = l2tp_nl_register_ops(L2TP_PWTYPE_ETH, &l2tp_eth_nl_cmd_ops);
304 if (err)
305 goto out;
306
307 err = register_pernet_device(&l2tp_eth_net_ops);
308 if (err)
309 goto out_unreg;
310
311 printk(KERN_INFO "L2TP ethernet pseudowire support (L2TPv3)\n");
312
313 return 0;
314
315out_unreg:
316 l2tp_nl_unregister_ops(L2TP_PWTYPE_ETH);
317out:
318 return err;
319}
320
321static void __exit l2tp_eth_exit(void)
322{
323 unregister_pernet_device(&l2tp_eth_net_ops);
324 l2tp_nl_unregister_ops(L2TP_PWTYPE_ETH);
325}
326
327module_init(l2tp_eth_init);
328module_exit(l2tp_eth_exit);
329
330MODULE_LICENSE("GPL");
331MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
332MODULE_DESCRIPTION("L2TP ethernet pseudowire driver");
333MODULE_VERSION("1.0");
334
