[net-next-2.6.git] / net / l2tp / l2tp_eth.c

/*
 * L2TPv3 ethernet pseudowire driver
 *
 * Copyright (c) 2008,2009,2010 Katalix Systems Ltd
 *
 *	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/module.h>
#include <linux/skbuff.h>
#include <linux/socket.h>
#include <linux/hash.h>
#include <linux/l2tp.h>
#include <linux/in.h>
#include <linux/etherdevice.h>
#include <linux/spinlock.h>
#include <net/sock.h>
#include <net/ip.h>
#include <net/icmp.h>
#include <net/udp.h>
#include <net/inet_common.h>
#include <net/inet_hashtables.h>
#include <net/tcp_states.h>
#include <net/protocol.h>
#include <net/xfrm.h>
#include <net/net_namespace.h>
#include <net/netns/generic.h>

#include "l2tp_core.h"

/* Default device name. May be overridden by name specified by user */
#define L2TP_ETH_DEV_NAME	"l2tpeth%d"

/* via netdev_priv() */
struct l2tp_eth {
	struct net_device	*dev;
	struct sock		*tunnel_sock;
	struct l2tp_session	*session;
	struct list_head	list;
};

/* via l2tp_session_priv() */
struct l2tp_eth_sess {
	struct net_device	*dev;
};

/* per-net private data for this module */
static unsigned int l2tp_eth_net_id;
struct l2tp_eth_net {
	struct list_head l2tp_eth_dev_list;
	spinlock_t l2tp_eth_lock;
};

static inline struct l2tp_eth_net *l2tp_eth_pernet(struct net *net)
{
	return net_generic(net, l2tp_eth_net_id);
}

static int l2tp_eth_dev_init(struct net_device *dev)
{
	struct l2tp_eth *priv = netdev_priv(dev);

	priv->dev = dev;
	random_ether_addr(dev->dev_addr);
	memset(&dev->broadcast[0], 0xff, 6);

	return 0;
}

static void l2tp_eth_dev_uninit(struct net_device *dev)
{
	struct l2tp_eth *priv = netdev_priv(dev);
	struct l2tp_eth_net *pn = l2tp_eth_pernet(dev_net(dev));

	spin_lock(&pn->l2tp_eth_lock);
	list_del_init(&priv->list);
	spin_unlock(&pn->l2tp_eth_lock);
	dev_put(dev);
}

static int l2tp_eth_dev_xmit(struct sk_buff *skb, struct net_device *dev)
{
	struct l2tp_eth *priv = netdev_priv(dev);
	struct l2tp_session *session = priv->session;

	l2tp_xmit_skb(session, skb, session->hdr_len);

	dev->stats.tx_bytes += skb->len;
	dev->stats.tx_packets++;

	return 0;
}

static struct net_device_ops l2tp_eth_netdev_ops = {
	.ndo_init		= l2tp_eth_dev_init,
	.ndo_uninit		= l2tp_eth_dev_uninit,
	.ndo_start_xmit		= l2tp_eth_dev_xmit,
};

static void l2tp_eth_dev_setup(struct net_device *dev)
{
	ether_setup(dev);

	dev->netdev_ops		= &l2tp_eth_netdev_ops;
	dev->destructor		= free_netdev;
}

static void l2tp_eth_dev_recv(struct l2tp_session *session, struct sk_buff *skb, int data_len)
{
	struct l2tp_eth_sess *spriv = l2tp_session_priv(session);
	struct net_device *dev = spriv->dev;

	if (session->debug & L2TP_MSG_DATA) {
		unsigned int length;
		int offset;
		u8 *ptr = skb->data;

		length = min(32u, skb->len);
		if (!pskb_may_pull(skb, length))
			goto error;

		printk(KERN_DEBUG "%s: eth recv: ", session->name);

		offset = 0;
		do {
			printk(" %02X", ptr[offset]);
		} while (++offset < length);

		printk("\n");
	}

	if (!pskb_may_pull(skb, sizeof(ETH_HLEN)))
		goto error;

	secpath_reset(skb);

	/* checksums verified by L2TP */
	skb->ip_summed = CHECKSUM_NONE;

	skb_dst_drop(skb);
	nf_reset(skb);

	if (dev_forward_skb(dev, skb) == NET_RX_SUCCESS) {
		dev->last_rx = jiffies;
		dev->stats.rx_packets++;
		dev->stats.rx_bytes += data_len;
	} else
		dev->stats.rx_errors++;

	return;

error:
	dev->stats.rx_errors++;
	kfree_skb(skb);
}

static void l2tp_eth_delete(struct l2tp_session *session)
{
	struct l2tp_eth_sess *spriv;
	struct net_device *dev;

	if (session) {
		spriv = l2tp_session_priv(session);
		dev = spriv->dev;
		if (dev) {
			unregister_netdev(dev);
			spriv->dev = NULL;
		}
	}
}

#if defined(CONFIG_L2TP_DEBUGFS) || defined(CONFIG_L2TP_DEBUGFS_MODULE)
static void l2tp_eth_show(struct seq_file *m, void *arg)
{
	struct l2tp_session *session = arg;
	struct l2tp_eth_sess *spriv = l2tp_session_priv(session);
	struct net_device *dev = spriv->dev;

	seq_printf(m, "   interface %s\n", dev->name);
}
#endif

static int l2tp_eth_create(struct net *net, u32 tunnel_id, u32 session_id, u32 peer_session_id, struct l2tp_session_cfg *cfg)
{
	struct net_device *dev;
	char name[IFNAMSIZ];
	struct l2tp_tunnel *tunnel;
	struct l2tp_session *session;
	struct l2tp_eth *priv;
	struct l2tp_eth_sess *spriv;
	int rc;
	struct l2tp_eth_net *pn;

	tunnel = l2tp_tunnel_find(net, tunnel_id);
	if (!tunnel) {
		rc = -ENODEV;
		goto out;
	}

	session = l2tp_session_find(net, tunnel, session_id);
	if (session) {
		rc = -EEXIST;
		goto out;
	}

	if (cfg->ifname) {
		dev = dev_get_by_name(net, cfg->ifname);
		if (dev) {
			dev_put(dev);
			rc = -EEXIST;
			goto out;
		}
		strlcpy(name, cfg->ifname, IFNAMSIZ);
	} else
		strcpy(name, L2TP_ETH_DEV_NAME);

	session = l2tp_session_create(sizeof(*spriv), tunnel, session_id,
				      peer_session_id, cfg);
	if (!session) {
		rc = -ENOMEM;
		goto out;
	}

	dev = alloc_netdev(sizeof(*priv), name, l2tp_eth_dev_setup);
	if (!dev) {
		rc = -ENOMEM;
		goto out_del_session;
	}

	dev_net_set(dev, net);
	if (session->mtu == 0)
		session->mtu = dev->mtu - session->hdr_len;
	dev->mtu = session->mtu;
	dev->needed_headroom += session->hdr_len;

	priv = netdev_priv(dev);
	priv->dev = dev;
	priv->session = session;
	INIT_LIST_HEAD(&priv->list);

	priv->tunnel_sock = tunnel->sock;
	session->recv_skb = l2tp_eth_dev_recv;
	session->session_close = l2tp_eth_delete;
#if defined(CONFIG_L2TP_DEBUGFS) || defined(CONFIG_L2TP_DEBUGFS_MODULE)
	session->show = l2tp_eth_show;
#endif

	spriv = l2tp_session_priv(session);
	spriv->dev = dev;

	rc = register_netdev(dev);
	if (rc < 0)
		goto out_del_dev;

	/* Must be done after register_netdev() */
	strlcpy(session->ifname, dev->name, IFNAMSIZ);

	dev_hold(dev);
	pn = l2tp_eth_pernet(dev_net(dev));
	spin_lock(&pn->l2tp_eth_lock);
	list_add(&priv->list, &pn->l2tp_eth_dev_list);
	spin_unlock(&pn->l2tp_eth_lock);

	return 0;

out_del_dev:
	free_netdev(dev);
out_del_session:
	l2tp_session_delete(session);
out:
	return rc;
}

static __net_init int l2tp_eth_init_net(struct net *net)
{
	struct l2tp_eth_net *pn = net_generic(net, l2tp_eth_net_id);

	INIT_LIST_HEAD(&pn->l2tp_eth_dev_list);
	spin_lock_init(&pn->l2tp_eth_lock);

	return 0;
}

static __net_initdata struct pernet_operations l2tp_eth_net_ops = {
	.init = l2tp_eth_init_net,
	.id   = &l2tp_eth_net_id,
	.size = sizeof(struct l2tp_eth_net),
};


static const struct l2tp_nl_cmd_ops l2tp_eth_nl_cmd_ops = {
	.session_create	= l2tp_eth_create,
	.session_delete	= l2tp_session_delete,
};


static int __init l2tp_eth_init(void)
{
	int err = 0;

	err = l2tp_nl_register_ops(L2TP_PWTYPE_ETH, &l2tp_eth_nl_cmd_ops);
	if (err)
		goto out;

	err = register_pernet_device(&l2tp_eth_net_ops);
	if (err)
		goto out_unreg;

	printk(KERN_INFO "L2TP ethernet pseudowire support (L2TPv3)\n");

	return 0;

out_unreg:
	l2tp_nl_unregister_ops(L2TP_PWTYPE_ETH);
out:
	return err;
}

static void __exit l2tp_eth_exit(void)
{
	unregister_pernet_device(&l2tp_eth_net_ops);
	l2tp_nl_unregister_ops(L2TP_PWTYPE_ETH);
}

module_init(l2tp_eth_init);
module_exit(l2tp_eth_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
MODULE_DESCRIPTION("L2TP ethernet pseudowire driver");
MODULE_VERSION("1.0");
Commit	Line	Data
d9e31d17 JC	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
bfc960a8	135	if (!pskb_may_pull(skb, sizeof(ETH_HLEN)))
d9e31d17 JC	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->last_rx = jiffies;
	148	dev->stats.rx_packets++;
	149	dev->stats.rx_bytes += data_len;
	150	} else
	151	dev->stats.rx_errors++;
	152
	153	return;
	154
	155	error:
	156	dev->stats.rx_errors++;
	157	kfree_skb(skb);
	158	}
	159
	160	static void l2tp_eth_delete(struct l2tp_session *session)
	161	{
	162	struct l2tp_eth_sess *spriv;
	163	struct net_device *dev;
	164
	165	if (session) {
	166	spriv = l2tp_session_priv(session);
	167	dev = spriv->dev;
	168	if (dev) {
	169	unregister_netdev(dev);
	170	spriv->dev = NULL;
	171	}
	172	}
	173	}
	174
f66ef2d0	175	#if defined(CONFIG_L2TP_DEBUGFS) \|\| defined(CONFIG_L2TP_DEBUGFS_MODULE)
0ad66140 JC	176	static void l2tp_eth_show(struct seq_file m, void arg)
	177	{
	178	struct l2tp_session *session = arg;
	179	struct l2tp_eth_sess *spriv = l2tp_session_priv(session);
	180	struct net_device *dev = spriv->dev;
	181
	182	seq_printf(m, " interface %s\n", dev->name);
	183	}
	184	#endif
	185
d9e31d17 JC	186	static int l2tp_eth_create(struct net net, u32 tunnel_id, u32 session_id, u32 peer_session_id, struct l2tp_session_cfg cfg)
	187	{
	188	struct net_device *dev;
	189	char name[IFNAMSIZ];
	190	struct l2tp_tunnel *tunnel;
	191	struct l2tp_session *session;
	192	struct l2tp_eth *priv;
	193	struct l2tp_eth_sess *spriv;
	194	int rc;
	195	struct l2tp_eth_net *pn;
	196
	197	tunnel = l2tp_tunnel_find(net, tunnel_id);
	198	if (!tunnel) {
	199	rc = -ENODEV;
	200	goto out;
	201	}
	202
	203	session = l2tp_session_find(net, tunnel, session_id);
	204	if (session) {
	205	rc = -EEXIST;
	206	goto out;
	207	}
	208
	209	if (cfg->ifname) {
	210	dev = dev_get_by_name(net, cfg->ifname);
	211	if (dev) {
	212	dev_put(dev);
	213	rc = -EEXIST;
	214	goto out;
	215	}
	216	strlcpy(name, cfg->ifname, IFNAMSIZ);
	217	} else
	218	strcpy(name, L2TP_ETH_DEV_NAME);
	219
	220	session = l2tp_session_create(sizeof(*spriv), tunnel, session_id,
	221	peer_session_id, cfg);
	222	if (!session) {
	223	rc = -ENOMEM;
	224	goto out;
	225	}
	226
	227	dev = alloc_netdev(sizeof(*priv), name, l2tp_eth_dev_setup);
	228	if (!dev) {
	229	rc = -ENOMEM;
	230	goto out_del_session;
	231	}
	232
	233	dev_net_set(dev, net);
	234	if (session->mtu == 0)
	235	session->mtu = dev->mtu - session->hdr_len;
	236	dev->mtu = session->mtu;
	237	dev->needed_headroom += session->hdr_len;
	238
	239	priv = netdev_priv(dev);
	240	priv->dev = dev;
	241	priv->session = session;
	242	INIT_LIST_HEAD(&priv->list);
	243
	244	priv->tunnel_sock = tunnel->sock;
	245	session->recv_skb = l2tp_eth_dev_recv;
	246	session->session_close = l2tp_eth_delete;
f66ef2d0	247	#if defined(CONFIG_L2TP_DEBUGFS) \|\| defined(CONFIG_L2TP_DEBUGFS_MODULE)
0ad66140 JC	248	session->show = l2tp_eth_show;
0ad66140 JC	249	#endif
d9e31d17 JC	250
	251	spriv = l2tp_session_priv(session);
	252	spriv->dev = dev;
	253
	254	rc = register_netdev(dev);
	255	if (rc < 0)
	256	goto out_del_dev;
	257
	258	/* Must be done after register_netdev() */
	259	strlcpy(session->ifname, dev->name, IFNAMSIZ);
	260
	261	dev_hold(dev);
	262	pn = l2tp_eth_pernet(dev_net(dev));
	263	spin_lock(&pn->l2tp_eth_lock);
	264	list_add(&priv->list, &pn->l2tp_eth_dev_list);
	265	spin_unlock(&pn->l2tp_eth_lock);
	266
	267	return 0;
	268
	269	out_del_dev:
	270	free_netdev(dev);
	271	out_del_session:
	272	l2tp_session_delete(session);
	273	out:
	274	return rc;
	275	}
	276
	277	static __net_init int l2tp_eth_init_net(struct net *net)
	278	{
3a737028	279	struct l2tp_eth_net *pn = net_generic(net, l2tp_eth_net_id);
d9e31d17 JC	280
	281	INIT_LIST_HEAD(&pn->l2tp_eth_dev_list);
	282	spin_lock_init(&pn->l2tp_eth_lock);
	283
d9e31d17	284	return 0;
d9e31d17 JC	285	}
	286
	287	static __net_initdata struct pernet_operations l2tp_eth_net_ops = {
	288	.init = l2tp_eth_init_net,
d9e31d17 JC	289	.id = &l2tp_eth_net_id,
	290	.size = sizeof(struct l2tp_eth_net),
	291	};
	292
	293
	294	static const struct l2tp_nl_cmd_ops l2tp_eth_nl_cmd_ops = {
	295	.session_create = l2tp_eth_create,
	296	.session_delete = l2tp_session_delete,
	297	};
	298
	299
	300	static int __init l2tp_eth_init(void)
	301	{
	302	int err = 0;
	303
	304	err = l2tp_nl_register_ops(L2TP_PWTYPE_ETH, &l2tp_eth_nl_cmd_ops);
	305	if (err)
	306	goto out;
	307
	308	err = register_pernet_device(&l2tp_eth_net_ops);
	309	if (err)
	310	goto out_unreg;
	311
	312	printk(KERN_INFO "L2TP ethernet pseudowire support (L2TPv3)\n");
	313
	314	return 0;
	315
	316	out_unreg:
	317	l2tp_nl_unregister_ops(L2TP_PWTYPE_ETH);
	318	out:
	319	return err;
	320	}
	321
	322	static void __exit l2tp_eth_exit(void)
	323	{
	324	unregister_pernet_device(&l2tp_eth_net_ops);
	325	l2tp_nl_unregister_ops(L2TP_PWTYPE_ETH);
	326	}
	327
	328	module_init(l2tp_eth_init);
	329	module_exit(l2tp_eth_exit);
	330
	331	MODULE_LICENSE("GPL");
	332	MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
	333	MODULE_DESCRIPTION("L2TP ethernet pseudowire driver");
	334	MODULE_VERSION("1.0");