l2tp: kzalloc with swapped params in l2tp_dfs_seq_open
[linux-2.6.git] / net / l2tp / l2tp_eth.c
1 /*
2  * L2TPv3 ethernet pseudowire driver
3  *
4  * Copyright (c) 2008,2009,2010 Katalix Systems Ltd
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/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 /* Default device name. May be overridden by name specified by user */
35 #define L2TP_ETH_DEV_NAME       "l2tpeth%d"
36
37 /* via netdev_priv() */
38 struct 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 /* via l2tp_session_priv() */
46 struct l2tp_eth_sess {
47         struct net_device       *dev;
48 };
49
50 /* per-net private data for this module */
51 static unsigned int l2tp_eth_net_id;
52 struct l2tp_eth_net {
53         struct list_head l2tp_eth_dev_list;
54         spinlock_t l2tp_eth_lock;
55 };
56
57 static inline struct l2tp_eth_net *l2tp_eth_pernet(struct net *net)
58 {
59         return net_generic(net, l2tp_eth_net_id);
60 }
61
62 static int l2tp_eth_dev_init(struct net_device *dev)
63 {
64         struct l2tp_eth *priv = netdev_priv(dev);
65
66         priv->dev = dev;
67         random_ether_addr(dev->dev_addr);
68         memset(&dev->broadcast[0], 0xff, 6);
69
70         return 0;
71 }
72
73 static 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
84 static 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
97 static 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
103 static void l2tp_eth_dev_setup(struct net_device *dev)
104 {
105         ether_setup(dev);
106
107         dev->netdev_ops         = &l2tp_eth_netdev_ops;
108         dev->destructor         = free_netdev;
109 }
110
111 static 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         /* checksums verified by L2TP */
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
154 error:
155         dev->stats.rx_errors++;
156         kfree_skb(skb);
157 }
158
159 static 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)
175 static 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
185 static 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         /* Must be done after register_netdev() */
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
268 out_del_dev:
269         free_netdev(dev);
270 out_del_session:
271         l2tp_session_delete(session);
272 out:
273         return rc;
274 }
275
276 static __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
286 static __net_initdata 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
293 static 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
299 static 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
315 out_unreg:
316         l2tp_nl_unregister_ops(L2TP_PWTYPE_ETH);
317 out:
318         return err;
319 }
320
321 static 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
327 module_init(l2tp_eth_init);
328 module_exit(l2tp_eth_exit);
329
330 MODULE_LICENSE("GPL");
331 MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
332 MODULE_DESCRIPTION("L2TP ethernet pseudowire driver");
333 MODULE_VERSION("1.0");